I see you have done some studying on the matter. I was fortunate to begin my undergraduate career before the term "plate tectonics" had been coined, though the pieces of the puzzle were already in place and the theory was (excuse the pun) primed to erupt. It did so before I ended my undergraduate career four years later.
None of the theories you mention, popular as each was in some quarters, were "generally believed". The truth is geologists at that time had no consensus as to what was going on with the gross structure of the crust. I started to outline this for you, but found specific names were escaping me, so I dug into my files and retrieved these notes I made a decade or two ago.
Many are aware that continental drift was actively promoted by the meteorologist Alfred Wegner following his publication of the theory in 1915[1]. His favoured mechanism (differential centrifugal ‘force’) was faulty, as was that (tidal forces) of an earlier proposal by Taylor[2] in 1910.
Although some researchers flirted with the idea of convection as the driving force, Arthur Holmes[3] was the first to place it on a solid footing (pun intended), as early as 1931. Despite his work and that of other visionaries, the idea continued to be rejected by the majority of Earth scientists.
There is no doubt that the American geological establishment was generally opposed to Wegner’s hypothesis. Yet this opposition was certainly not unanimous. Two examples will illustrate this.
Alexander Logie du Toit received a substantial grant from the Carnegie Institute of Washington for a study of the Atlantic coast geology of South America, with a view to comparing and contrasting it with that of South Africa. Recall that Wegner had noted such similarities.
The powerful influence of and necessity for a uniformitarian approach is revealed in this cautious observation in the introduction to Hess’s History of Ocean Basins:
I shall consider this paper an essay in geopoetry. In order not to travel any further into the realm of fantasy than is absolutely necessary I shall hold as closely as possible to a uniformitarian approach; even so, at least one great catastrophe will be required early in the Earth's history.
The point in all this is that the balance of opinion was against drift, because the balance of evidence failed to support it. This began to change in the late 1950s and early 1960s as growing evidence forced a reevaluation.
There were two strands to this. Firstly, there was now clear evidence for divergent polar wandering, best explained by continental drift, from the research of scientists such as Blackett[4] and Runcorn[5]. Secondly, seafloor spreading from mid-ocean ridges was posited by Hess[6] and expanded upon by Dietz[7], and demonstrated through the analysis of magnetic anomalies, first by Mason[8], then by Vine and Mathews[9].
By the end of the 1960s these threads had been pulled together, by the pioneering work of the likes of Wilson[10], Morgan[11], McKenzie and Parker[12], and Le Pichon[13]. Plate tectonics was born. (The phrase was first used in print by Morgan and McKenzie[14] in a 1969 paper in Nature.)
[1] Wegener, A. (1915)
Die Enstehungder Kontinenteund Ozeane. Vieweg, Braunschweig
[2] Taylor, F.B. (1910)
Bearing of the Tertiary mountain belt on the origin of the Earth’s plan. Geol. Soc. Am. Bull. 21, 179–226.
[3] Holmes, A. (1931)
Radioactivity and Earth movements, XVII. Trans.Geol.Soc.Glasgow, Vol.XVIII–Part III, 1928–3118, 559–606.
[4] Blackett, P.M.S.(1956).
Lectures on Rock Magnetism. Weizmann Sci. Press of Israel, Jerusalem, 131pp.
[5] Runcorn, S.K. (1956).
Palaeomagnetic Comparisons between Europe and North America. Proc. Geol. Assoc. Canada 8, 77–85.
[6] Hess, H.H. (1962).
History of Ocean Basins. In
Petrologic Studies –A Volume in Honor of A.F. Buddington, pp.599–620
[7] Dietz, R.S. (1961).
Continent and ocean basin evolution by spreading of the sea floor. Nature 190, 854–7
[8] Mason,R.G.(1958).A magnetic survey of the west coast of the United States between latitudes 32◦and36◦N, longitudes 121◦ and 128◦ W. Geophys.J.Roy.Astron.Soc.1,320–9
[9] Vine, F.J. & Matthews, D.H. (1963).
Magnetic anomalies over oceanic ridges. Nature 199, 947–9
[10] Wilson, J.T. (1963).
Hypothesis of Earth’s behaviour. Nature 198, 925–9
[11] Morgan, W.J. (1968).
Rises, trenches, great faults, and crustal blocks. J. Geophys. Res. 73, 1959–82
[12] McKenzie, D.P. & Parker, R.L. (1967).
The north Pacific, an example of tectonics on a sphere. Nature 216, 1276–80
[13] Le Pichon, X. (1968).
Sea-floor spreading and continental drift. J. Geophys. Res. 73, 3661–97
[14] McKenzie, D.P. & Morgan, W.J. (1969).
Evolution of triple junctions. Nature 224, 125–33
Returning to the specific examples of contrasting theories and consulting my 1960 (2nd Edition) copy of de Sitter's Structural Geology I find he lists six major theories to account for orogeny (mountain building). He subjects these to a critical examination and his concluding remarks, not just of the chapter, but of the entire book are worth repeating here:
The principal feature of our future work as geotectonicians should be in the direction of providing the geophysicists with a better and more diversified picture of the actual succession of deformation phases, which is essential to an understanding of the origin of the different kind of orogenes and other structural units of the Earth's crust.
Ironically geology is a young science. Young sciences begin by being descriptive long before they become explanatory. What de Sitter was saying here is that in the 1950s, as far as geoteconics was concerned, it was still a young science, engaged in description. There was no theory that "generally believed". individual scientists might promote their favourite hypothesis, but the consensus was a shoulder shrugging "who knows".
Science progresses three steps forward, one step back. Once in a very long time a Khun paradigm shift may occur and we walk back half a mile, examining the path taken, discarding some of it, repairing this bit, adding a smoother surface here. But there is continual progress, a narrowing of the options of possibility. That aspect is all too often overlooked.
So, I wholly agree with you that science discards ideas no longer supported by evidence, but where we differ - I think you may attach too much significance to this, perhaps because you overestimate the scope and significance of the change. And for that scientists are often to blame. After all what scientist would not wish to say, "My discovery quite overturns our previous understandings of the matter and is really a revolution in the field. May I have my Nobel prize please?"