Please do tell me more about how shielding in Falcon's jab range is a good idea. Do you use it often in practice ?
Well as I said before you can't really abuse your spotdodge like you would do against some characters, it's not hard to hold A on reaction to it. And what do you mean by moving backwards ?
Wrong, in the worst case scenario Wario ends up offstage without one of his best recovery tools because he was grabbed while trying to destroy his bike.
And the bike doesn't prevent grabs, obviously.
I don't know why so many people behave like ******* when it comes to the bike, but to me it's pretty clear : the moment this item lands on the stage the status quo of the game changes.
If Falcon is smart he will protect the bike instead of trying to break it, and if Wario tries to get near then it's just a good opportunity for a grab. If Wario doesn't try to approach it then good, it makes his offstage game far more vulnerable.
Tricks like extended hitboxes and bike Dtoss combos only work on people that don't know about the mechanics of the item, but if it's not the case and the Falcon knows what he's doing he's either too far for it to matter or close enough to get a free dashgrab.
Same deal for the tires : if Falcon shields them, the worst that can happen is a grab from Wario.
If Wario is staying close to the ground he's staying in Falcon's dash grab zone, just saying. And neither of both characters should be taking unnecessary risks.
But I agree that Wario has better tools to edgeguard Falcon (not that Falcon can't edgeguard Wario or that he can't deal with Wario's edgeguard) and that Wario kills easier (though his kill options don't beat shield).
Hum, those are 2 of the 3 aerials that get straight out ranged by Falcon's Uair, Bair and Utilt.
And then again, playing keeping away is nice and all but that means you must have the lead. Falcon too can keep Wario away when he has the lead, even if you don't seem enclined to believe it.
Have you ever been raptor boosted for retreating a whiffed aerial right next to Falcon before ? Because that seems like a perfect opportunity.
As it's the only way to proactively get a grab on Falcon, it's surely a good idea sometimes, given that we get much more than he does from a grab at the percents where we care to grab in the first place. In my experience, I haven't done it much, because weaving and moving away both seem to benefit me more (though they're also easier to adjust to, since that's a lot of Wario's general gameplay), and I don't get to play Falcon that much (though I use him fairly often myself). I am remarkably bad at avoiding stuff and getting grabs, but I know other Warios who are certainly more proficient at it.
Spotdodge for Wario in this matchup is only good for making Falcon think twice about going for a standalone grab. His airdodge is much more effective in general because of the kind of control he maintains in mobility and speed. As far as moving backward goes, I'm talking about the same kind of camping you're talking about in walling out Wario, I imagine. Stick out hitboxes and protect your space, but if things get sour, you can usually reset the situation. Pivot grabbing is always safe for every (non-tether) character forever, retreating spacing options allow safety and a decent ability to threaten, etc.
Outside of specific matchups (like, King Dedede), I don't see much of a threat in not having your bike for recovery. Wario's recovery without the Forward-B is still about average when comparing it to the cast, mostly by virtue of his great horizontal aerial mobility (stupid airdodge). SDI edgeguard hits up and you won't have a problem with getting gimped unless you're bad and spoiled on your recovery. No Wario player who understands the situation would put himself at risk of getting grabbed by Falcon in order to break his bike; it's not at all worth it. The bike mostly stands to prevent Jab, which has already been mentioned as your go-to counter for a fair amount of Wario's possible options, as well as the only reliable way of landing a grab. As a result, this makes spotdodging much more potent, as a spotdodged grab should always be a free grab for Wario here, and Falcon's long-lasting hitboxes are generally unsafe as burst-range options.
Tires also stop autojab (slightly useful via Z-Drop; makes Falcon have to think about it a little), frame-trap landings and recoveries (especially when it's pretty predictable, as Falcon's tends to be), can prevent grab-release stuff when thrown into the air, and a tire on the ground can also prevent opponents from Jabbing, which would count as slight stage control. It's more than fair to say that the bike on the stage can have a substantial effect on the match, but it definitely doesn't help Falcon as much as many characters.
All of Falcon's (and most characters') grabs last for two frames. It's definitely easy to mix up via normal fall and fastfall (as Wario will most certainly be shorthopping around, regardless), rising and retreating aerials, and spotdodge in general, which is also made even more unreliable due to the input delay. Also, it's definitely outranged by pivot grab, which is a problem for Falcon doing standalone grabs in general.
Wario's ability to weave will still make counterplay unreliable if Wario mixes it up (though Falcon does get a lot out of successful hits), and B-Air will still catch you sometimes as a result.
The difference between keep-away is that Wario can actively benefit from the time going down, especially with his having to work less to deal damage and KO on average, the bike being a useful means of getting Falcon to want to fight (apparently), both bike and tires being slightly-to-somewhat useful here and there, as well as Waft always being a factor. Falcon only benefits from it if he's winning when the timer hits zero. I'll take my chances.
I know that a N-Air moving toward Falcon will hit him out of Raptor Boost, and that if Falcon uses it in a position to punish whiffed aerials, Wario can definitely bait it out with an empty jump and get much more out of it than Falcon would if he lands a Raptor Boost.
I once struggled with this matchup; I also thought it was relatively even at one point. Then I realized that if you change your play significantly (stay close to the ground, don't worry about applying much pressure in most situations, wait for Waft, don't fear having the Bike on stage), it gets much harder for Falcon. It's not just theorycraft; this isn't a matchup I've never seen in years or anything. I've done it, and I'm confident that it works well. Outside of general range, Falcon doesn't have a whole lot on a Wario that knows how to move well in this matchup.