Reddit has many different subs that suffer from its problems in different degrees, so there's still islands of relative calm and sanity, usually in low-traffic subs. To some extent this was also true of different sites in the overall StackExchange network, but SO itself always dominated the network, it was designed and run as a monoculture, and that culture was, well ... gestures vaguely in SO's direction

It’s very easy to destroy a specific sub (if it’s not too big and doesn’t have half a dozen mods).

it's like those ddos rings, but works on social networks.

You can create a sub and a Discord group, then ask people in the Discord group to launch a mass report against your competing sub and its moderators. You can use scanners to find questionable stuff that you can report, and more often than not, this will get the mod banned. If the sub doesn’t have multiple mods (with unique IPs, as Reddit tracks fingerprints), the sub is now in the hands of Reddit’s mod team.

Back then it was not this easy, but now with AI and residential IPs you can create lots of fake users and reports etc... and take almost any avg redditor down.