Smashboards

I've spent the vast majority of my time with Ultimate online-I love competitive, but even before quarantine my family was really busy and I couldn't get a ride to tournaments very often, monthly at best. And the best piece of advice I can give to you is to find a smallish group with mostly good connections and play each other through Discord/Facebook and arenas.
Elite Smash does nothing for anyone in the end except for making bad players with bad connections feel better about themselves. Stay away unless you have no other alternatives. Anther's Ladder is also a good alternative, it's like a ranked matchmaking system that deliberately tells you how good your opponent's connection is before you spar.
Anyways hope this helps a bit.

I would agree, but we probably have different reasons for hating online. I rarely get disconnection errors, and as to actual bans, even more rare.

Lag is the reason I stopped playing Smash online. I haven't played online Smash since the Smash Ballot days during Smash 4.

There's always going to be some sort of lag. That's a given. The problem with Ultimate is that there's already some built-in input lag as it is, and then you couple that with the buffering system, the actual online lag with the fact that so many moves have low cooldown.