Literally ordered three of those "large" Thermalright nvme heatsinks, but my reasoning is a little different:
It's not just about cooling down the nvme, Im going to try them our because of proximity heat. Most of my builds are ITX, and motherboard manufacturers, for whatever silly reason, stick all sorts of hot things between the CPU and GPU. I've got one B550 motherboard where the southbridge heatsink Literally stretches under the Nvme, and then comically tries to wrap a heatsink over the top of the nvme with a block (with like no fins) of aluminum that contacts the rest of the SB heatsink with two little screws. No thermal pad, nothing. Just two little screws to attach a block of aluminum, which is probably 2/3rds the total size of the SB heatsink, to the rest.
The nvme heatsink that comes with the board is also pretty pathetic, given that it's supposed to be Under that SB heatsink block.
So, my thinking is: since the SB heatsink block is likely going to do almost nothing anyways, I won't screw it onto the rest of the SB heatsink, nor will I use the included tiny nvme heatsink. I'll allow the SB heat to soak into the NVMe, but hopefully sink all that heat and the nvme heat away with the large Thermalright nvme heatsink. I've even got a few different fans to try on it as well, in case I'm not happy with the sound and/or performance of the included fan.
Hopefully my logic holds up. I'll hopefully be building again soon so I'll figure it out.