If this is using Chrome it’s likely because Meet uses non-hardware accelerated codecs there. Under Safari it’ll use accelerated h.264 and be much easier on battery.

This comment caught my eye - because I'm using Chrome too.

Is there a way to enable hardware accelerated codecs in Chrome + Meet?

(I have no idea what that means, I'm just quoting you)

I checked my Chrome settings and "Use hardware acceleration when available" is enabled for what that's worth.

Not sure. There’s extensions that force YouTube to serve h.264 so it seems like something similar should be possible with Meet.

Doesn't seem right. I used Google Meet for a few hours the other day and it was still at 93%. This is a MacBook Pro M2