The thing with M.2 heatsinks is depending on the use case, they can actually be worse for thermals. Most M.2 drives are mounted directly under, or very close to GPUs. Heatsinks are just a radiator and they do not discriminate on what heats them. When your gaming the heatsink just heats up in the high ambient temperatures around the GPU and M.2 slot and cause drive temperatures to rise.
My M.2 drive can often hit well over 60C while running MSFS for example, and the game isn’t even running from it. It’s because it’s mounted in the exhaust path of the GPU fans and the M.2 heatsink just takes it all in and dissipates it directly into the drive.
Of course, all the benchmarks of SSD with heatsinks show them to be great - because they test in them in open air test benches under heavy, sustained I/O with no GPU load.