I don't think so in upcoming 5-6 year this is possible. Because there are lot's of coins which are being trading under BTC. There are many ICO and upcoming projects which are coming under Bitcoin. So it will be very hard to break it for any altcoin. There are chances for being in top 10 currencies if the project is good and real. But Bitcoin is a mother currency and it will be always on top.
There is acceptance of bitcoin worldwide and even many big platforms or trading firms are taking their steps in the world of Bitcoin. Likewise, ETF is near to approve by SEC for bitcoin. So all this things will bring bitcoin towards more up in terms of acceptance and mass adoption.
In many countries even some people don't know about other cryptocurrency than Bitcoin. So it will be very hard to break Bitcoin in near future.