No, it really isn't.
Differences:
1) Reddit is super ban happy, and there is no way to view banned content. Ban reasons include slurs, political opinions, as well as no reasons at all.
2) Subreddits are not filters over the same content, they have (mostly) different content.
3) There is a fractal abundance of user-moderated subreddit; yes, there is some bad culture in some of them. This is not what ACX is proposing. He is proposing 2-20 filters, ran by the company, not by volunteers, with a specific purpose and clearly defined.
I really don't see how ACX's proposal can cause illegal behavior or harassment that is not already there.
You're making a false equivalence with reddit, then pointing out reddit has negative emergent properties.
And also, whether they're justified or not, it doesn't really matter to he point. ACX's proposal =/= subreddits.
"Reddit has a paid team called Anti-Evil Operations (part of the "Trust" & "Safety" team) which goes around permanently banning accounts for saying bad words. We made automod block them so you don't lose your account for saying a word and getting reported. It's not our rule, it's the entire website now, we're just trying to look out for our people. Sorry."