I am using a Silicon Power P34A80 M.2 NVMe SSD for over 2.5 years now and temps. have been problematic since the beginning. But it's much worse nowadays. In basic workloads, even in gaming it's fine but in case of sustained transfers even low bandwidth like over MTP which is limited to USB 2.0 it throttles hard after a few minutes or so. Reaches 80-85°C easily.
So I am thinking of investing in a heatsink. Those available on Aliexpress mention 2mm/4mm etc. thickness. Obviously the thicker ones would be better but I can't fathom how much the laptop can accommodate? Will even a 2mm thick heatsink fit?