Totally, even within the same company it can vary. I worked some place where engineering was really good about encouraging people to take time off and lots of upper management set a good example with unlimited PTO. However, I had heard that sales and consulting weren't as encouraged.

It can work well, but I think it comes down more to the your manager/org than the overall company (assuming we're talking about a large enough company for there to be disparate orgs). We have unlimited PTO and I think I took 7-8ish weeks last year—including spending pretty much all of November in New Zealand. Nobody had an issue with it.

OTOH, I know of people in the company who struggle to take more than two weeks.

During my last job search I would point-blank ask the hiring manager how much PTO they and their reports took in the last year.

It's undefined vacation with manager approval, who internally enforces a hard limit set by HR.