Yes. The most recent I know of is Tet 1968. I think one of the 1948 Israeli offensives in their war of independence was timed for that too.
Nonsense. The Tet offensive was timed, like many other military attacks, to take advantage of the holiday, like Trenton in 1776, or the 1973 Yom Kippur War, or 10/7. The psychological part you’re talking about is hindsight. I don’t know what you mean by 1948, those were just normal counterattacks.