While one of the intended uses was P2P cash, which is not very practical due to high fees, it is indeed successful as a long-term store of value.

If you ignore the stomach-churning 80% drawdowns and instead look at the long-term average, there's a power law that explains the price quite well:

https://digitalik.net/btc/long_term_power_law

The problem is that in economic terms, there hasn't been a "long-term average" yet. It's a new financial instrument, and during what duration it's had, its price has been driven by an influx of interest.

At best, you can hope for a logistic curve, where the growth will flatten off when everybody on the planet (at least, those with money) has collectively decided to accept it. That will level off the price.

At worst, when that happens, the people who depended on the exponential growth will cash out their earnings in search of new opportunities. If that happens, the entire thing will crash rapidly.

I can't tell you which it's going to be. I'd call it a coin toss. But that makes it hard for me to consider it a "long term value". It's a valid best case scenario, but we haven't seen that best case yet, only an influx of new buyers who are drawn more by the upward curve rather than the potential flattening.

You were able to say the same about beanie babies. Bitcoin could lose trust in it at any time. There’s hardly an intrinsic use in a Bitcoin and there’s also hardly any demand for it except as a gambling opportunity. (Fiat money has government demand through taxes).

I don't necessarily disagree with you, but OP was talking specifically about adoption, which appears to remain very low. It seems the only practical use for Bitcoin today is as a store of value. Which can be rephrased to mean that it's a tool of speculation for those wealthy enough to buy it.

Who will pay for the gains if people want to withdraw them?