Does using a case with iPhone cause excess heat to linger around and does it have any significant impact on battery life? I bought an iPhone 11 around 3 weeks ago and I’ve been quite paranoid about using a case as I read somewhere that over the long term it can continuously cause excess heat to not be dissipated effectively and can degrade the battery much quicker. Does anyone know how true this actually is and if it will have a significant impact? Having quickly destroyed the battery on my old iPhone, I was wondering what I need to do differently this time around.
Whether or not the case can cause a thermal problem depends entirely on the case.

Is it possible for a case to impact battery life by not dissipating heat - yes.

Is that true for any case - no.

Imagine a well fitting case made of a metal - it would easily dissipate just as much heat from the phone as when not using a case.