if by "legitimate" you mean something that the government approves then you are wrong this is not the bitcoin goal either.
Why would anyone assume "legitimate" means "government-approved"? Legitimacy is not a legal concept.
there is a simple explanation for it, people don't care about altcoins!
We heard the same about Bitcoin...
the purpose of bitcoin is still a long way so I think bitcoin has not reached its destination, if seen from the current price bitcoin slightly cheaper than the highest price he ever reached. but I think the bitcoin progress is not just there and still far more results to be achieved.