It's becoming trendy, so people book larger suites instead and also so the hotels can save money on doors and easier for housekeeping. They're getting rid of shower doors too.

Nate Barzgate does a good bit on it: https://www.youtube.com/watch?v=kgtgjA_UiAo

I stayed at a super fancy hotel in Napa for a work event that didn't even have a WALL separating off the bathroom it was just a half-partition sheer panel thing.