How do you enforce this without putting an undue burden on the community? There's a fundamental disconnect: it's near-zero effort to leave drive-by strafing run trash (a negative, hateful, or stupid comment) without some kind of registration system. So the effort to clean up the trash, and the effect it has on the community, is disproportionate. Littering becomes way too easy.
Littering already is "too" easy for TDWTF commentors, and somehow the website has persisted without being buried in garbage. (I haven't been the one who had to take out that trash, but @apapadimoulis doesn't seem to think it is a huge problem, either.)
Too much emphasis on easy anon also doesn't encourage people to join the community except in a superficial way, and is kind of negative for the health of the community in the long term. Everyone is "just passing through", so why would they care about anything there?
This logic seems front-to-back to me. People sign up and contribute if a community is (or seems like it will be) worthwhile. Making people contribute doesn't improve the community, if anything, it seems like an admission that the community can't sustain itself with voluntary participation.
I hope you'll relent and implement some type of anon with configurable user names. That has been part of the fun all these years, but for the longest time, I could not register on the front page, and had no choice but to be anonymous. Discourse has been a breath of fresh air.