Luigis speed is overrated. He can cover a lot of ground fast but he moves in the air slow, falls slow, and his dashdance is too small to cover the startup of his wavedash. His wavedash is good and carries him as a character but it cant make up for the precission you get out of a dashdance. The startup for his wavedash is actually a weakness and since he kind of uses his wavedash as a replacement for a dashdance, then you could say his dashdance is slower to control than other characters. Luigi doesnt use his speed in the same way a fox or falcon would. He doesnt have the ability to quickly change directions and manuever around other characters offense like fox or falcon
Yes, I agree with a lot of these points and that's why he's not regarded as high tier. He has a limited neutral game because he is only fast on the ground, and making the opponent play your game and taking advantage of that speed on the ground is what good Luigi players are doing and it's helping them get these placements. The matter of wavedashes being inferior to dashing as a form of ground mobility definitely has its merit and it's another limiting factor of Luigi but I believe we can be far more accurate with wavedashing than we currently are and that will only serve to increase the strength of Luigi as a general character.
I also hate the word strawman but it's useful because everyone knows what it is and has attached a negative connotation to it, so if I point out that someone is setting up a strawman it should signal to them that their argument is invalid as a response to mine and they need to come up with relevant points or concede.
@Xyzz
I don't think the start up times on his moves are too bad. There are faster moves out there but Marth is balanced in that his marginally slower speed is made up for by his generous range.
I don't want you to think that without high-tier speed a character is bad. It's like distributing stat points in an RPG. Marth has less speed in certain areas, but bloated range works against that problem to make his neutral game tighter.