Seeing code that goes all in on OOP absolutely makes me cringe as I know it generally means the unit tests are going to be more complex than they would be in an FP environment, the code's likely going to be harder to extend as there's no amount of class inheritance planning that can prepare you for all future business requirements, and in most cases it's just going to be so much more verbose than an FP solution would be (I know this last point is a bit of a personal issue).
Code that goes all in on FP I absolutely love on a pure nerd level, but absolutely hate on a practical level. Pure FP is neat in the same way that seeing someone who can calculate out pi to a hundred digits is neat. Sure it's impressive, but like... I got this calculator that will handle it much easier.