Its because btc are still mined, there'll be a point where its no longer worth it to mine the btcs and it will cost basically no energy.
Yes I'd rather invest my money in a currency that is worth more and more every year (on average) instead of printed paper trash aka US$.
Also, y'all are obsessed with elon!
Perhaps YOU would invest in a currency which is ON AVERAGE worth more every year as long as you make the average sufficiently large, but if it's gonna work as a currency, YOU wanting to INVEST in it isn't enough.
Also, if what you are saying does happen, ie that BTC will become so much more valuable, then it's gonna be worth it to start mining it again. It would basically be a massive resource dumpster, just dumping more and more energy into producing something completely unnecessary, which it basically already is, but 10 times worse. Hurray for le future!