The resistance to tearing out a bad abstraction isn't just cultural: combining two different functions into one is a lossy operation, which makes splitting an abstraction harder than creating it in the first place.

While the functions are distinct the call sites are self-documenting. You know which calls are for which purpose because the names are different. After combining them to deduplicate the code, you've lost that information, and to disentangle the abstraction now requires you to infer and reintroduce that lost information.

It's not that it can't be done, but there is real friction that doesn't just exist in people's heads.