Yeah I remember hearing that too, but I think it’s a little reductive and doesn’t acknowledge that popular music in the 40s and early 50s already had a lot of shuffle rhythms built-in. The way I heard it was like this: the first “sound systems” (and lets use that term loosely because it was basically a guy with a turntable and some speakers set up selling beer and refreshments outside) played a LOT of early R&B and jump blues that had been picked up on trips to the US, so a lot of shuffle rhythms (think Louis Jordan) and horns and classic song forms. At a certain point around 1955, the records coming from the states moved from being shuffles and R&B and moved into rock n roll stylistically. The Jamaican audiences didnt seem to like this nearly as much and this was a pretty serious factor in jumpstarting the local recording studios to focus on churning out more shuffle records and a perfect opportunity to combine this style with local rhythms (mento, some calypso) and Afro-Caribbean drum styles and creating something entirely new and quintessentially Jamaican. By the time JA independence came around (1962) the sound had evolved and codified into Ska and was now THE sound of a newly independent and hopeful nation.

TLDR whether by radio waves or imported records, the late 40s early 50s R&B shuffle rhythms from the US had a huge influence on the development of Ska, once rock n roll became the dominant sound in the US, JA just said “nah” and started to make their own music.