BTC gains value by usage, it is not an asset at all, it is a way of trading value securely without centralised banks
Where it looks like an asset is, in the early years of the transition from fiat to BTC, going to show up the ones who sat on their coins and sold them for fiat
But if the whole world accepted BTC what are you going to sell it for?
As it becomes accepted down supply roots i.e. ; coffee shop owner sells you cups of coffee for BTC because they can buy beans for BTC because the bean farmers can buy fertiliser and tools and pay workers in BTC and the workers can buy food and pay rent with BTC. I'm missing out a few steps but you get the idea.
With any luck in some years we may be able to leave this fiat shite way behind us...
A lot of debate exists about this. There's no value to be gained if BTC is primarily a currency, much like investing in currencies isn't a thing people do. People speculate on currencies to take advantage of short term differences in value between two currencies but if you hold Euros, you're not earning a return. BTC could very well be an asset class if it remains an "alternative currency" to fiat options. If it replaces fiat options we'll see the currency reality you're predicting.
Even as a currency, it could go up in value. Just like we hold cash now, people would hold bitcoins. And the more people there are holding them, the more their value goes up.
It's an interesting experiment, to be sure. But keep in mind that the reason the dollar is inflating is because people are holding and the government keeps printing more to cover debts (or something along those lines. If everyone spent all their money, the debt, I believe, would be nonexistent due to significant taxes, which would be funneled back into the economy).