Bitcoin will remain the only solid coin. The only coin that survived for the longest time (other coins can't claim this unless they invent a time machine).
There will be alts that pump really hard and make people millionaires, but no alt is going to surpass Bitcoin's strength and solidity. No coin will get a bigger marketcap. In the long term people holding 21+ BTC will be rewarded by history with rich-tier status for seeing the value in it before most people did. Do not let the FUDsters trick your mind or the trolls try to derrail the excellent job being done by Core devs.
Let's continue then our path towards inevitable triumph.
We can still say that Bitcoin has no competition in terms of IT'S VALUE. We can say that Bitcoin's value is really hard to achieve because of the fact that it became a basis for other Cryptocurrencies to be their basis for initial prices. If we consider their platforms in terms of the usage and availability for people's demand, we can still say Bitcoin's platform is useful for creating transactions and creating payments but of course, there are a lot more usable platforms other than Bitcoin and some of them are really making their way up to be known.