What makes you think Luigi doesn't lose to any of them?
Do people really still think he got overall buffed instead of nerfed from the last patch?
And also, even if Luigi didn't lose to any of the new top tiers (and Sheik, ZSS and Rosa got super nerfed where they can't do anything anymore)... why would you ignore some of the lower characters that could have an advantage over him? If Luigi never reaches the top because of not being able to go through lower characters then his MUs with tops wouldn't matter as much.
And not losing to characters but going even with them is pretty okay if you ask me.
Luigi hasn't done anything notable since evo. Concon might've gotten unlucky with SDing, but we don't know how much higher he would've gotten if he won, and what has Luigi done since?
Luigi is still overrated I guess by some and hated by so many people even though he doesn't do anything anymore, while Sheik reigns supreme with ZSS' slowly taking over anything else that's left, and no one's saying a word about it.
Why did no one cry about Luigi preDiddynerfs? Luigi was always like that since the Wii U version came out. Because everyone already had Diddy to cry about? Luigi got beaten before by more than one character, and now it's still like that.
Why do people cry so much about Luigis dthrow to cyclone, while ZSS and Sheik could also get hoo-has for as long as Diddy could?
Everyone and their mother has throwcombos to a kill in this game. Don't just cry about some. Cry about all of them or accept that this is how this game was made (and they probably made at least some intentionally) or don't cry about any of them. [or at least... cry about the ones that make the actual best characters in the game even better [hint: Luigi isn't one of them]]
Characters in the game that could still receive (small) nerfs because they're too strong [imo]: Sheik, ZSS, Luma
Everyone else seems fine for now. Even though a few do still have a few broken attributes to them, but they should probably not just get weakened, but also buffed somewhere else to compensate for that, unless you just want those characters to die off.
Although this could remove some of their uniqueness and mash all characters together even more.
If Luigi is so easy to play then play him, win and be happy about your win if you manage to do that, because it's not as easy to actually win as you might think, if you have good opponents at least.