One thing to keep in mind is that while there is indeed plenty of speculation, there's also plenty of healthy criticism of the current valuations as well as outright doomsday talk from fairly well known investors.

What this means is that for now the market continues to self correct and we haven't reached peak positive sentiment yet. Historically, massive selloffs happen because of unexpected sudden changes in sentiment (2000, 2008) or due to black swan events (2020). Given that we just went through a black swan and the markets aren't overly optimistic, I wouldn't expect a large crash in the immediate future.