I deleted my Reddit account and made a new one after my ex messaged me, it's a reasonable precaution and good opsec if you don't feel comfortable with people having an easy time tracking you. I want to avoid doing that here if I can though. I don't know to what extent a record of the things you've said can pseudonymously establish status as a unique person given the way AI is changing things, but the other options seem to involve trusting untrustworthy entities or giving up on the internet entirely so it seems worth trying.