Men of Playgirl

I don't know is it because they are from the 1990s but all these models look so tacky and without any sex appeal. .
There's definitely been a shift over the decades. In the 90s, porn and nude photography was almost all studio-based, and relatively bigger budget (hair, make-up, wardrobe... if required). You can mostly put it down to it being pre-internet, pre-smartphone, pre-digital camera. These days it is hugely DIY, there's more of an appetite for amateurs, immediacy and authenticity or at least the appearance of it.

It might look tacky by comparison, but it was expensive and needed a long lead time and big financial output to put a magazine to print, so you wouldn't risk it with low budget photography.