TriTails
Smash Lord
Except he never was really considered Top 5.to be fair, Luigi went from argued Top 3-5 in some instances to somewhere in the 15-25 area, so his nerfs were actually pretty substantial
People were agreeing he was overrated af. He was mostly placed within Top 10-15 territory (Often times, just 'high tier' and not 'top tier').
But yes, his nerfs were huge with little to no compensation. But his mains have been getting results lately (Mostly in Top 16 echelon) and that's pretty nice for the arguably the most nerfed character in S4 history (And by 'most nerfed' I mean the impact of the nerfs overall. Sheik and Diddy for example, survived rounds and rounds of nerfs. For Luigi it was basically one nerf and down he went).
I think the character is in upper mid, because his MU spread isn't as nice as other high tiers. So yes, that's quite a fall from Top 10-15 position. But hey, the character's still doin' work, I'm not complaining.