The people who pay big money for collectibles usually fit one or more of these profiles:
a) Super-competitive men who are often more interested in preventing someone else from acquiring something than they are it acquiring the item themselves.
b) People who acquire something rare with the intention of flipping it for a profit to one of the unsuccessful bidders.
c) People who have too much cash; they want to diversify into other holdings that have value.
d) Middle-aged affluent men who want to either re-acquire something they owned in their youth, or to acquire something they once really wanted, but couldn't or didn't have.
e) Geeks and incels who want to impress others similar to themselves.
If I had major lotto money I think I'd get back into stamps. I'd stick with jerk countries, communist/fascist. They often have interesting looking propaganda.
Don't really care if anyone else has them.
No intention of flipping it, if plausable I'd go for a complete collection and flipping ain't it.
Again no plans to sell so not party if diversification which is otherwise important, also not a fan of collectables.
I did collect stamps as a youth but never seriously, never focused, just got those bags of international used stamps and see what the cat dragged in.
I know plenty of geeks and forever alones [no Incels(TM)], and much like my kdrama and bwood thing they would all think it's weird. Also no homo.