Falcon has to actually get reads and bait air dodges to get kills though(or yolo raptor boost/smash which are much more punishable than grabs so they demand a lot more thought to weigh the risks). Yea, falcon is easier to control but having to control luigi is much easier than having to know how your opponent is controlling their character.
Technically, everyone need a read to KO off people. Like, you can kill people off a D-throw with a kill setup, but it also takes a read to actually land the grab. Alhough, I agree on how Falcon get KOs harder than Luigi.
Its complexity of the game plan on top of execution for me. Luigi wants to move in, get grabs, and do guaranteed damage in advantage. It's easy to understand what should be happening (application) and its easy to physically perform it (execution.)
Not to be putting you or any other Luigi players on blast, I play Luigi too and I feel that the weakness of playing a character with a basic game plan is that he gets countered by very basic strategies. So you have to be pretty creative and exceptional to make up for this at a high level most of the time.
Luigi does have to take risks because of how dead he is if he ever ends up off stage even with his massive reward.
This is what I meant. Luigi's typical strategy is very easily countered by other basic strategies. This forces Luigi to do stuffs other than just mindlessly spamming Fireballs and grabs that is very effective on low level players but stupid to do at high level.
IMO, this is what makes Luigi not as braindead as people would think. His options have counterpicks, and getting punished can mean terrible disadvantage as he has no good options landing to the stage and his recovery is so easily exploitable, so he has to take risks doing his stuffs. But this is my opinion so yeah.
Luigi only edgeguards in two ways, ledge drop bair for stage spikes, or semi spike cyclone.
This is false. There are tons of ways you can edgeguard with Luigi. Even if most of them don't guarantee kills, they are effective on pestering people off-stage or straight up murders weaker recoveries.
- F-air: Obvious. Can also stage-spike at lower percents.
- B-air: Also obvious. Stage-spikes much more consistently than F-air and also kills at reasonable percents [read: Early] but have much more risk due to end lag.
- D-air: Another obvious thing. Even if it doesn't spike it sends people at semi-spike angle.
- Fireballs: Messes with momentum, so they are effective on the likes of Falcon, Link, or LM. Even if they airdodge we can still hit them with F-air. Can also Flare Guard by bouncing them off walls.
- Rev. U-air: At higher percents this sends people at semi-spike angle. Kinda like Ganon's tipman but not as effective. If you're lucky you may even be able to chain with a B-air.
- Cyclone: Obvious, but very difficult to do. And also, it's not a semi-spike, I'd call it a soft spike because semi-spike is different thing entirely.
- Meaty N-air + things: Not guaranteed and situational, but 6% hit of N-air combos to everything and the meatier it is, the better.
And I don't believe if Luigi can't go deep. He in fact can go really really deep thanks to Cyclone. You just have to watch your DJ so it doesn't burn out because you do something silly.