To be fair, the SEC has only really gone after cryptocurrencies other than Bitcoin, which is the only major blockchain that uses the energy-intensive Proof-of-Work. The things the SEC was trying to regulate, that it considered securities, are almost entirely running on Proof-of-Stake networks, which have negligible relative energy consumption.
This will almost certainly have a lot of other negative impacts, but I doubt it will have that much on the climate.
If you ever find that an artist on other platforms isn't on Bandcamp, you'll usually find them on Qobuz's Download Store since that's a common place that they also tend to publish.
It's a little less convenient than Bandcamp, and is often a little more randomly priced across artists and even individual songs from an artist, but if your goal is to compensate them and get a high quality audio download, it'll be another option.
They also have a streaming offering with way better payout rates for artists at what tends to be around $0.01873 per stream as of last year, in case you're not ready to ditch streaming, though I can't speak to how good it is as I haven't tried it myself.