The thought came to mind after reading a recent post about Baldurs Gate 3 here but it reminded me of the Japense only PSX game Mizzurna Falls where if you don’t perform a certain action early in the game you are prevented from getting a true ending. While this might not be a traditional soft lock because you can still progress to a point it made me wonder none the less.
I understand BG3 might be a hard lock because the game abruptly comes to a close I am not going to get into the semantics. The only other soft locks I can think of are with Pokemon.
Shout out to the fan translation of Mizzurna Falls. An article on the ROMHacking.net website can be found here.
There are a LOT of these, especially from the 8/16/32 bit era.
https://tvtropes.org/pmwiki/pmwiki.php/Main/UnintentionallyUnwinnable