We need an economy that isn't denoted on dollars or euros or similar. Bitcoin is a step towards that. And all the PoW "waste" is worth it. (Though I wish there was a better alternative that's more environmentally friendly while still decentralized like PoW so PoS isn't a good candidate)
But note "assets" and "savings accounts" are not the same thing, and confusing the two is pretty bad.
Gold -> Good, and Bitcoin is like Gold in many aspects. While it doesn't have Gold's history yet, it has a few other qualities like easy transferrability and divisibility.
Other assets -> Like? ForEx is at the mercy of issuing government (just ask Russia who lost ~300B$). Land can be seized if it's outside one's jurisdiction.
In general, Bitcoin (like Gold) is a great asset to park some fraction of your wealth as a hedge against geopolitical risks.
If I put money in my savings account, I can use it tomorrow. If you put money in your BTC savings account a year ago, your BTC is worth less than money under a mattress (or in a modest yield savings account).
You may want to invest in BTC, and that's absolutely fine! But it's not a savings account.
Market forces don't really discriminate one innovation over another by whether it's socially desirable to you or me.
Using power for bitcoin means it's not available for the next best use. It's all about opportunity costs.
Stranded power means power with a very low opportunity cost. But not necessarily zero (or negative).
As a thought experiment: think about what would happen, if bitcoin moved to a proof-of-stake system tomorrow.
It's not an either/or thing.