No matter how much people use or adapted Bitcoin but still there's always cons that's why altcoins existed because of bitcoin having cons. One of it is the speed of a transaction getting confirmed unlike the altcoins which us faster than bitcoin. I think one of the reason why bitcoin is still at the top is the time or how long bitcoin existed. I know that you know how long bitcoin existed or what year it is created. Anyway, it also depends on the person on what crypto they will use in the end.