I've definitely posted to the same subreddit with two different accounts by accident without being banned.

The android reddit app annoyingly doesn't check for account matches. If you click a browser notification link on Account A it can open a reply form on App account B.

I meant if one of the accounts is already banned there, it counts as ban evasion and Reddit bans all of your accounts.

This might easily happen if you like to participate in political discussions.

In hindsight, I understand. But I did this 6-7 years back and no one has come after me, should I care at this point?

Anecdotal but I've noticed Reddit has gotten very ban happy in general in the past year.

I actually gave up using it because, perhaps in part because I'm behind a VPN (required in my country), any new accounts I create get banned very quickly once I start commenting.

I haven't been able to create a Reddit account by any method in years. It always happens in one of two ways: you create an account and instantly get the red banner at the top of the page saying you're banned, or you create an account, post a few comments, notice nobody's replying to you, try loading your profile page in private browsing and it says you don't exist (a shadow ban).

There's nothing of much value on that website, but sometimes I try creating an account to comment on something.