This clarifies it I hope? It has audio & proper phonetic alphabet spelling for US vs UK.

https://dictionary.cambridge.org/pronunciation/english/yacht

Assuming it's similar to "folly" vs. "foley".

Not even close.

Care to expand?

Sure: “yaht” and “yot” sound virtually the same (at least in American English), only maybe slightly different in the length of the vowel; “folly” and “foley”, on the other hand, sound very different from one another.

Yes, that is my point. "Yot" is pronounced differently (as in "foley") outside of America in a lot of cases.