This is my view exactly. I've been telling people I know who are trying to ride the crypto train that BTC has no fundamentals, by which I mean exactly that "the only reason it has value is if people value it."
Think about it: the way BTC is created is basically by expending energy to solve some contrived math problem. So what? Who should ever care at all that someone, at sometime in the past, happened to be running a computer that hit on the solution of a silly math problem? It gets even more absurd when you consider that mining pools became a thing, so that even if your particular computer hits on the solution, you didn't actually do all the work that goes into the so-called "proof of work." (Yes, I know, in this scenario, the new BTC is split among the pool members, but, that doesn't really matter very much.)
So, basically, BTC is the recording of the fact that someone, somewhere contributed to the solution of a math problem. Why should that have value at all, over and above the inherent value in solving said problem, which is essentially nil in this case? Well, it shouldn't. And, yet, it does, for the reason you've noted.
Although I hesitate to call BTC "money," there is an actual form of money that also has value for the same reason, is a true digital currency, which has a durable and distributed transaction record, and is much easier to manipulate for the purpose of managing an economy based on it. That would be the USD, and other such fiat currencies. And, the USD fundamentally is just the recording of the fact that a bank somewhere has managed to create $9 by turning $1 in reserve into $10 in loans out into the economy at large (or, whatever the ratio exactly is -- I forget.)
In other words, if you accept that BTC is a currency at all, it's little more than a worse version of the world's de facto reserve fiat currency, with the added bonus of generally not being able to transact using it, along with extreme volatility relative to the USD, which one actually can transact with.
That's not to say I don't wish I had bought some BTC back when I first heard of it and it was trading at under $1. Had I gambled even $500 on it back then, I would have somewhere in the neighborhood of $9M now, and, essentially be set for life. But, I was a poor graduate student who already realized most of what I previously mentioned and decided that I'd rather pay rent for a couple of months in the dorms than buy an expensive lottery ticket.