Lemmy is having some stability issues across its instances because of this growth curve: https://lemm.ee/pictrs/image/693866c7-8f65-4046-8781-58aee70...
That said, I've had a burner email for as long as my personal email for this very reason. I even have 2 burner gmails. It's not exactly a huge invasive measure like a phone number (which I'd never give to a site that isn't trying to take payments. Hell, still haven't given Amazon my phone number).