The transition is not straightforward, and with what's at stake they absolutely need to take their time to get it right; they only get one chance.

I don't really use Ethereum, but I commend the devs for recognizing the problem years ago (before I was even aware of it) and taking steps to remedy the situation.

In the short-term, yes, it is incredibly wasteful (though recent changes have disincentivized mining somewhat, even with a bit of protest) and there are many other cryptocurrencies which are already proof of stake available. This year, hopefully, Ethereum will finally move to PoS.