I did an search for this guy and it seems he may be a fraud.
Thanks for your research! I also looked into his profile, and haven't heard of any of these societies. While
MENSAMensa (the most popular "high IQ" society) is mentioned
here, this is also just on that suspicious website, and there is no
MENSAMensa source itself I could find.
There is also this Reddit thread:
https://www.reddit.com/r/korea/comments/1i2l8ov/is_dr_younghoon_kim_a_fraudscammer_allegedly/ The first response (with many upvotes) is quite clear:
276 IQ doesn’t exist. Most serious institutions assessing IQ will stop at 160 because it’s already such a small sample from the average intelligence that any further assessment is fairly approximative. Depending on the methodology (most IQ test use a SD of 10 or 15 points), you are already between 4 and 6 SD away at that point.
Even if his score is legit by whatever measure they took, he seems to be a "mind sports specialist", which means that he may have a very specialized kind of intelligence. Such people can also excel in other fields but it's not a must.
Personally I think his decision is not the worst (I believe Bitcoin can still grow a lot) but far from being the best (doing DCA, to catch a better entry point).