> I draw the opposite conclusion here. In monoliths, someone else might want the code to stay in the codebase. I don't want to ask everyone about it. Everyone's responsibility is no-one's responsibility, and the code stays as is.

Then they can retrieve it from source control? Leaving dead code in the codebase because "someone else might want it" sounds like nonsense.

It seems usual to leave code in the codebase (possibly commented out) if you think it may be used again in the near future. It's easier than digging through source control. If you know you won't need it any more, then you delete it

Then substitute 'dead code' for 'buggy code that someone else likes'