All this time and until now, the entire cryptocurrency has been solely as a gasket between the dollar and the user. After all, so smart people once decided to use BTC as money and shout about it everywhere, on every corner, but at the same time when they saying "Bitcoin" they mean "the number of dollars for 1 coin".
Markets are pretty efficient. They price in speculative probabilities, like Bitcoin's future utility and adoption as a mainstream payment rail. If that's a real possibility, of course people are going to buy them up, knowing the limited supply is going to force the price exponentially higher in any mass adoption scenario. That's just a market being a market. You think everyone is going to wait until Bitcoin is perfect and ready to place their bets? Of course not.
I don't think that means Bitcoin is limited to being a speculative vehicle. It just means speculation comes first, results come second.
BTC is already a speculative tool - just like any other at least slightly popular cryptocurrency. Buy " smth" cheaper and sell a little more expensive - this is called speculation. Only in the case of cryptocurrencies, this is the highest level because here demand and supply are not born out of material meaning, but only because there is a demand for easy money and cryptocurrencies give an offer for this easy money (and good ideas for some people who believe in bright money feature).
You can even say that cryptocurrencies are now not far away from derivatives on derivatives and other bets on top of other bets.