I see your concern and a lot of the people in the comments here who think alt coins will gain more adoption make great points. I was talking to a buddy of mine the other day and he, as a bitcoin fanboy, was also getting worried about the potential of the altcoin takeover. His only glimmer of hope is in side chains.
I don't fully understand the mechanics behind it, but he suggest that bitcoin may 'win', so to speak, because all of the novelty and efficiency that altcoins give us can be implemented in a bitcoin sidechain. The essential idea is that you can use bitcoin or any other side coin to make a transaction on a blockchain other than your own. In other words, exchange Bitcoin for Sidecoin without the need for another party to trade with.
That said bitcoin hasn't been updated in.... 2 years now?
https://gendal.me/2014/10/26/a-simple-explanation-of-bitcoin-sidechains/
RE: HODL was BAD for the TULIP MANIA