It was always more of a theoretical concern.
At least since 2014 onward.
Best thing is, even if somebody did it it wouldn't affect the coins in your wallet.
Worst case: a transaction is first confirmed, and then not there anymore in the new chain.
People used to wait 6 blocks before considering a transaction final to guard against that. (And the possibility of accidental non-attack chain splits)
Waiting 6 blocks is still a thing.
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Yeah sure you can wait as long as you want 😇
But I would consider a transaction final after 2 blocks.
Maybe 6 if you sell a house or some other expensive things 😉
IIRC 2 blocks deep orphans still happen occasionally
