DNA was not discovered on LSD: https://psychedelicpress.co.uk/blogs/psychedelic-press-blog/...
When I was a teenager, I heard the claim and believed it. All these musicians and artists I looked up to did psychedelics! So I took psychedelics! What I came to find, however, was that all of those artists had some sort of classical training early in life and a decade of working hard touring/painting and building their professional practice. The drugs came after, not before.
I'll grant that stimulants may have made positive contributions. Oh how I love/hate stimulants.
The Beatles were highly skilled musicians before taking drugs, but it seems reasonable that attempting to recreate the psychedelic experience on tape pushed them towards new sounds and techniques that they wouldn’t have otherwise tried.