It's always possible that another cryptocurrency could overtake crypto.
It is not impossible, at the same time, the possibility of it happening is very minute. The fact that btc is first crypto launched, it will for a long time be the most valuable crypto reason being that it has more widespread popularity among crypto enthusiasts, and being the pioneer coin, it is more likely to be considered for adoption by any government or enterprise.
Satoshi created bitcoin to solve the problem of trust with governments and to be a store of value that can be sent/received anywhere/anytime without permission or trust of anyone else.
Amongst many other reasons why bitcoin was created, this is one. Others are;
- to make transaction from different parts of the world between people faster.
- to digitalize the currency. etc