... the first of a new thing often gets credit for introducing that new thing, even if by later objective measures it seems overrated.
In 1964 when The Beatles visited America the best-selling album of the year was "Whipped Cream and Other Delights" by Herb Alpert and the Tijuana Brass. (Unlike the Beatles, Herb Alpert released a new album in 2023.)
In 1965, the best-selling album was the soundtrack to "The Sound of Music".
Those aren't bad albums, but they sound nothing at all like popular music since then. The Beatles, rightly or wrongly, seem to get credit for that shift.
Coming to The Beatles decades later, they sound pretty much like many other bands of that era and even a bit old-fashioned compared to most. They're not bad and they've got some catchy tunes, but it's hard to conceptualize what it must have been like to hear modern pop music for the first time when you were most likely to hear The Tijuana Brass on the radio.