PS4 slim is pretty silent though.
In general, yes.
In some games it sounds like a jet engine in the first couple minutes.
Uncharted 4 and God of War, when I started those after not playing for a while I feared my PS4 Slim would take flight from my bedroom and head to the airport.
That's one thing I noticed, and it might be just my own impression, is that if I started a game I didn't play in a while it would be the worse, but if I played it again the next day it would be much quieter.
It also gets a lot hotter than I would like it to be, the plastic actually starts making cracking sounds when it gets too hot.
But I had zero actual problems with it.
The fan noise would be lost in the game sound anyway, and the heat never made it even freeze or much less shut down.
So I can't complain.