It's definitely a mixed bag across the industry and even across individuals at the same company. To some people culture fit might mean "I'd hang out with this

It's definitely a mixed bag across the industry and even across individuals at the same company. To some people culture fit might mean "I'd hang out with this person on Sundays." This of course is problematic and can let in all kinds of biases leading to discrimination. Ideally culture fit is about whether a person can fit in to the processes in place. Do they value testing? Are they comfortable with the level of ambiguity that will be found in their assignments? Etc. I'm in favor of the latter, but it needs to be evaluated based on direct questioning to limit the impact of biases i.e. "Would you be comfortable being required to have 100% test coverage on the code you write?" I've certainly seen folks come out of an interview confident that someone wouldn't be comfortable with ambiguity just because they said that at their current job they are given detailed specs to implement.