Probably worth noting that the throttle applies to write speeds not read from what I have seen, so gaming will be unaffected since it's loading data off the drive not writing to during gaming. The other side of it is, are you really going to notice a real world difference even if it was throttling from 3GB/s to say 1.5?
I'd personally still only have a small stick on heatsink on the controller itself. Cheap and keeps the sustained write heat generation controlled. The throttle temp is 85 degrees ish going by the Samsung Magician software graph too. Up to 80 degrees is shown as "normal" on the Samsung software so really I wouldn't worry about it at all.
Looking at mine right now, over the last few days the max temp in normal usage with both Lightroom writing, video editing (writing to the drive) and games installing etc, the max temp was 68. Al my case fans are at around 600rpm for quietness as a reference.
