It's interesting that you say this. Outside of some early experiences with Melee (I think) that I never owned, Brawl was my first Smash game and I don't like it nearly as much as Ultimate either. I think that had a lot to do with how uncomfortable it was to play on the wii controller though.
Why don't you like pvp?
I used the Gamecube controller to play Brawl, because yeah, the Wiimote was not really designed with games like that in mind. Ultimate I played in handheld mode - like basically everything else on Switch - and it wasn't quite as comfortable as a Gamecube controller, but still comfortable enough for me to not hate every second of it, haha.
I don't like PvP for a couple of reasons. I've found that when I play PvP titles there is often such a disparity between my skill level and someone else's (either way, although with common PvP genres like fighting and racing games my skill level is dramatically below my opponent's, because they're not the sort of game I generally play) that it means it isn't even going to be a contest. Losing repeatedly is very tiring and not much fun - I'm not a sore loser, but I do play games to win - and there's no real entertainment in winning constantly either. That, plus in my experience PvP leads to a lot of hostility between people and I'm really not a competitive sort of person anyway. It's just...not fun.
Even if I wanted to play with random people I wouldn't, because I don't like the way competitive Smash is played. Too much dodging, arena throwing, edge grabbing, etc etc - I've watched a few matches and it doesn't look like much fun at all. I understand that it's very technical and requires a lot of skill, but it doesn't make for the greatest gameplay, at least in my opinion. All the rules and whining about what is "fair" and what isn't bothers me as well: one of my favourite things to do in Melee with friends was to turn off every item except for Pokeballs, crank items up to max, go to the Pokemon Stadium level, and spend the match - stock, not time limited - lobbing them and seeing what came out. Would people online play that way? I doubt it. People take it so seriously, which is about as far away from fun as is possible for me: if I want to take a game seriously, I'll play something like Disgaea, where I can lose myself in grinding and statistics. A fighting game, for me, would be something quick I'd play to unwind and relax (kinda like how I play Warriors titles, actually) not something I want to get caught up in...that's incompatible with Smash PvP.
...and yeah, I don't have any friends to play with now. If I had a group of friends I was comfortable with who were around the same sort of skill level with these games as me, I expect it'd be a lot of enjoyable. It was with Melee, where it was literally anyone's game. But I don't, and I've been out of the genre for so long that I'm awful at them comparatively and I don't really have the motivation or interest to practice and improve when it's not a genre I really enjoy to begin with.