Not sure why you expect bitcoin to do "high returns" for everybody, that was never a promise and never a goal. Are you going to argue that stocks are not fair because you personally didn't buy the stocks with the best returns?

Bitcoin only makes one relevant promise: There will only be 21 million. And that means that the people who are born poor get a chance at building wealth by not having the government constantly reduce the value of their money. Bitcoin is an escape from the system that keeps people poor.

You could say as much for beanie babies too. They will be limited so therefore valuable. Forget a hundred years from now that people might not see any value at all in a plush doll, or some runescape gp, or bitcoin. Meanwhile, something like iron or gold has held value for all of human history.

Scarcity alone does not make something valuable, things that are useful have value. Happy to clear that up.