The Real Tester for the Holist Approach in Science is surely Cosmology!
For, such is essentially only an "observation-only" sub-discipline, wholly without the absolutely necessary confirmatory contributions of Experimental Interventions, to verify-or-deny any Purely Speculatively-arrived at Theories, that investigators in the field are surely initially-restricted to. Unless, that is, there are confirmatory experiments, that would be possible in the Laboratory on Earth, and in the always-required controlled conditions, and hence could confirm relations revealed, which would also be applicable within Cosmology too.
Now, so-called Empty Space and Laboratory situations delivered, of course, the major differences in Ground, between those two very diverse environments involved. For, if Space really were totally empty, normal situations upon Earth, most certainly, were NOT! So, experimenters often established their experiments within totally evacuated environments, by both establishing and maintaining a vacuum, in which to carry out their experiments. And, for a while, that seemed to suffice.
Until, that is, James Clerk Maxwell embarked upon his major study of Electromagnetism, when he needed a defined Spatial Medium to help him adequately address his Subject: for without it he would be unable to complete his decided-upon task: it certainly wasn't a set of Properties of Nothing, and literally all useful prior contributions required such a Medium!
So, Maxwell decided to first model an invisible Substrate, entirely via what effects it definitely had upon all Events occurring within it. And then, he used his new definition of "The Aether" to attempt to solve his outstanding problems in Electromagnetism.
For many decades, this seemed to work, and much sound work was completed in this area. But, then the Michelson-Morely Experiment seemed to prove that no such Universal Substrate existed in Space - yet Maxwell's discoveries, predicated upon such a Medium, nevertheless carried on being used, BUT now in supposedly Totally Empty Space!
Needless-to-say, Physics then began to fall-apart as a solely Causally-Explicable Discipline, and fitted-up more and more Mathematical Formulae, which increasingly replaced Causal Theories as "supposed explanations"! Indeed, Henri Poincaré and Ernst Mach, with their Positivist Approach, which they called Empirio Criticism, then suggested that only an amalgam of Explanations AND Mathematical Formulae could deliver, theoretically, the objective Real Physical World.
And, by the time of Niels Bohr and Werner Heisenberg, the wholly mathematical Copenhagen Interpretation of Quantum Theory replaced all Explanation at the Sub Atomic Level!
But, this Descent had been inevitable: for, ever since the Greek Intellectual Revolution in the 5th century BC, and the establishment of the very first Rationally-Consistent Intellectual Discipline of Mathematics, with such evident theoretical power, within that discipline, it was exactly what could possibly revolutionise both General Reasoning and the Sciences, so it was wholly illegitimately transferred-over to both of these areas too!
Why was it illegitimate?
It was totally Pluralistic: so all its Laws were Eternally FIXED (as they were legitimately in Mathematics)! But, they are NOT so Fixed in either Everyday Logic or in The Sciences, as they are not fixed in nature.
And such was a major restriction on the ability of all these Important Disciplines to cope with Reality and its evidently self-moving Actual Development.
Yet, at almost the same time as the Greek Intellectual Revolution, in India, The Buddha was formulating Mankind's initial effort at describing and using Holism, which also, and crucially, began to address Qualitative Changes, which were wholly inexplicable within the Pluralist Approach.
Indeed, though The Buddha, and his followers could never complete what was necessary to equip Holism to also address all the issues across all Disciplines, it did significantly position Qualitative Change as the engine for all Real Development of the wholly New, and, it is not surprising that the best of his followers were acclaimed for their evident Wisdom: the Loka Sutta is a case in point, of the alternative reasoning of the Buddhists!
Now. it is clear that Mankind did not come Ready-made into existence, but evolved out of its animal prehistory, finally into a Thinking Species: and, as such, we had to Change Qualitatively, but NEVER directly, to ever better conceptions of their World. But, the climb could not be cumulative! Conceptions were never wholly correct, but always a mixture of better-and-useable ideas, along with others that were wholly wrong. And, to make matters worse, the flaws in the mostly correct ideas, contradicted the as yet unrealised features, in the rest, and worked against a speedy extension.
And also, both the prestige and the power resided unavoidably with the Pluralists, because of their extensive successes in mastering the world with Technology, and its valuable products: it predictably, via western Empires eventually ruled the World, until Holism re-established itself in a surprisingly Political garb - initially in the writings and actions of the historian Karl Marx. who began to establish a profound analysis of Economics in his lifes work, Das Kapital!
But while he certainly pointed the way towards a modern and scientific Holism, the absolutely crucial comprehensive application to The Sciences was never undertaken.....
Elsewhere, this philosopher has completed a major holistic critique of the Copenhagen Interpretation of Quantum Theory, but the time has come to also address the mess that is present day Cosmology.
There is NO available Technology in Cosmology, especially as the whole of recent excursions into Space have been totally dominated by Pluralist "scientists" and technologists: absolutely no departures from the Fixed Laws of the Pluralist Approach have been allowed in their investigations of the cosmos.
So, when added to the above-described inabilities of Cosmology to even establish anything Explicable about our Universe, the clearly evident failures of present day version of it, cannot be hidden behind successful Technology: but they certainly try to do that!
From the Big Bang and constantly the Expanding Universe, to Dark Matter, Dark Energy and Black Holes, it is clear that Pluralist Speculation had nothing-of-value to contribute from that actually-existing Universe, to contradict the Pure Speculations, without any confirming-or-denying evidence from a properly investigated Reality, as they are unavailable to earthbound and pluralist-constrained thinking of the so-called "scientists" involved.
Until Modern Holist Thinking tackles these areas of study, as is becoming increasingly available on SHAPE Journal, Cosmology can never break out of its current manacles. And even Modern Physics as it is developed and taught currently, is incapable of having anything but an increasingly confusing and misleading approach to Reality-as-is!
The contradiction, on Earth, between Pluralist and Holist Approaches to Real Science, will be the initial battleground!
The fight has begun with the latest Special Issue of SHAPE Journal, dedicated (along with many other contributions in previous issues), to explaining the recent 21st century contributions to Modern Holist Science.
The current research is still at an early stage, but will carry on for the foreseeable future, as this undertaking is only one of the many offerings regularly available on SHAPE - with of course, many political contributions, and topics such as the Covid 19 Pandemic, and the now substantial Economic Crisis worldwide too.