There were no Luigis in the finals of evo and smash con, results seem to indicate he's struggling for some reason. Either people are learning to deal with it better or the fact that he was just nerfed is had made all of his matchups noticeably harder, or both.
Also the double standard is real. Why does Luigi get to be a top tier when he is so easily counterpicked he can't go solo? There was just like two pages of people saying if you can't go solo or deal with sheik you're unviable, full stop. Luigi can do neither of these things.
If he was so easily counterpicked he wouldn't have good local/regional results like he does, no?
And yes, people are learning to deal with him better, at least arguably in a similar way that's happening with Rosalina.
Honestly, Top Tier seems to really only fit the likes of Sheik. Maybe Sonic, Diddy, ZSS (going by varied regional opinions/results).
Otherwise it's just a big fat high tier, or top-tier minor, because there are many characters which can claim high tier "power level" right now [Ike, etc] it's hard to place them on the same level as the one's we know are "high tier".
It's possibly a double standard, but *pick random perceived solo viable character*
Do they lose to Sheik? Bar ZSS, Diddy, Sonic and Fox, no one else can claim they do not right now (imo).
Do they lose to Luigi?
My name is Diddy. So yes.
My name is Fox. So yes.
My name is Pikachu, so yes/yes.
My name is Sonic, so maybe and maybe (leaning yes).
My name is Rosalina, maybe leaning no and no. But my match ups aren't necessarily good everywhere else though
Hi, my name is Luigi, I like long slides on the beach and I'm losing to Sheik just like everyone else is apparently, but destroy a long list of characters.
Luigi's "hard match ups" aren't being seen in tournament frequently. But those characters who could do find themselves getting buffs in the patch cycle though.
If someone were to make a tier list in the most "logical" fashion right now, it would be hard to put Luigi in a different tier to the characters we're seeing with similar result spreads and perception of "strong match ups".
However, fireball nerf may be enough to really show that he isn't on that pedestal I'm implying. But not enough time has passed in my opinion to know it's certain (his results aren't worse than pre-patch from what I see?).