Essentially, OO forces you to think of everything as an object. That pattern is valuable at times, but the way you think about something and the patterns you're familiar with intrinsically shape your approach and how you can solve it which can be a bad thing.

OO is not bad; it's merely bad to only use OO, to teach it as the only methodology in schools, to use it to the exclusion of all else. Like most things, OO is just one of many options and is not always the best one.