To your point about the Beatles as hypsters with some talent, you have to realize that no 'hype machine' existed back then. In the U.S. 'social media' consisted of movies, T.V. AM radio--not even FM yet--and printed newspapers and magazines.

People had to sit in theaters to see movies. Today, social media seek us; back then, people had to seek out media.

T.V. did come into homes, but in the early 1960's in the U.S. there were three choices: CBS, ABC, or NBC. All three were very culturally conservative: when Elvis Pressley performed on T.V. the 'suits' wouldn't allow his rotating, undulating pelvis to be shown. (The Beatles did nothing remotely like that.) T.V. went 'off the air' following the late news: 11:30 PM. If you turned on the T.V and dialed it to any of those three stations all you got was a 'test sign'.

Their looks and their personalities played a big part in the success of the Beatles, but more than all else put together it was plainly and simply how damn good their songs were--and innovative--and culturally referential, starting with the Rubber Soul album (released in late 1965).