Pixel was slowing down - case caused it

I bought a Caseology Parallax a couple of months ago and didn't think of it twice. The case is made out of TPU and it's pretty rigid and thick. My phone has been very hot every time I take it out of the case and I have been noticing some slowdowns and lag that seemed to completely go away when the phone cooled down again. So I tried going caseless and the slowdowns and lag has completely disappeared. It seems like the heat can't dissipate right when it's trapped between the thick layer of plastic that is the case. I've now ordered a bumper case which doesn't cover the back of the phone instead. If anyone feels like their Pixel used to be faster, try going caseless for one day, the difference is very noticeable if you have a thick plastic case.