I remember a lot of discussion about that topic of Bitcoin ownership

And the skeptics are totally correct, there can't be more than 20-40 million "true" Bitcoin owners if there are only 40-50 million addresses with BTC on it. (Sidechains would make that possible, but they are not massively used. and you could also argue that the sidechainBTC are "not Bitcoin".)
But on the other hand, there are over 300 million Binance accounts and over 100 million Coinbase accounts according to their own reports. And there are also polls where e.g. about 15% of US citizens claim to own "cryptocurrencies". This may include stuff like memecoins and NFTs however, i.e. not much more than play money.
So my personal estimation is that there may have been, in total, 100-200 million Bitcoin users, but only a minority (20-40 million) of them owns them really and has an own private key. The rest either 1) has BTC on an exchange, but never owned it really on-chain (I'd say that could be 50-70 million at least), 2) owned BTC in the past, and 3) own some derivatives like ETFs, ETPs, sidechains, wrapped BTC etc. (a few million).
But now to the topic question which is independent from the question how many users exist now:
A duplication of Bitcoin demand of course has happened already several times. From all the estimations I've read, since 2020 such a duplication should have taken place. And in 2020 also a big percentage of BTC have been mined. But every day, some people sell their Bitcoins, or a part of them. They simply think the price is attractive, either because they're early adopters and can now buy a house with their profit, or because they panic and they think it may go lower. Or whatever. You can't buy Bitcoins without someone selling them (if you're not a miner).
So I'd say if the adoption duplicates again, I'd say the price would evolve like between 2020 and now. That means, it would increase between 3 (late 2020 to now) and 10 times (I think we can ignore the March 2020 dip). This is of course because Bitcoin has a low circulation rate, and many simply HODL. And thus the additional demand would push the price much more to the upside than if Bitcoins were sold more often.