It's a really complicated transition, but it's already started. The estimate is that there's probably about $1.5B worth of transactions left to mine, but most transactions will be switching over to PoS in the coming year. No one knows for sure when the full transition will occur, it's more of a gradual phase-out.

I like Ethereum not just because of the more responsible PoS but also because mining is currently asic resistant. A lot of the waste going into bitcoin right now is building specialized miners that will go into a landfill after a generation or two. Eth can still be mined with hardware you already own.

It's coming with Ethereum 2.0. The transition process to Eth2 is on the way, it is estimated that they will finish by 2022.