I just went to an ifixit store. They opened the back of the laptop. They disconnected the wires from the key/touchpad and plugged it in again. now my everything is working fine again! oh and their service was for free. So it’s worth a try.

Thought I've got water damage or something but luckily I'm not the only one. I've got Big Sur running for a while now, but since the last update (currently running 11.4) the trackpad and keyboard freezes after sleep sometimes. A reboot after holding the power button solves te problem for a few hours. Got a 13" MBP early 2015 model and never experienced issues before. Good to read apple takes this problem seriously :)...