I'm somehow unsure now… I just read on the Internet that this should actually be the perfect room temperature. Nevertheless, my laptop now takes a lot longer to start up properly and is also much slower in the first 10 minutes than when I have it in the living room at 23 degrees. It even crashed yesterday.
I don't think that matters in any way, at most your laptop will burn your legs when it gets hot. But if you really have concerns, you should take a look at the thing. As I said, the room temperature is irrelevant in this regard.
It can't really be due to the temperature. 15 ° C is not too low, it is often "better" when the temperatures are low.