. . .Lucky_Sharmz19, have you played Roy before? O_o
Roy's aerial attacks are not worthless. . .because of his falling speed and because his aerials' relatively fast execution time (mostly f-air I'm talking about here), he has amazingly fast shffls. In that respect, Roy can be rather fast, as he can execute a large number of shffl'd attacks in a relatively short amount of time. You've seen Roy shffl'd u-air juggle a Fox before, right?
And range is still an issue here. Yes, Roy's range is for the most part neutralized because he has to spend the majority of the time at sweetspot range, which is at the middle of the sword. . .but his overall sword range--sweetspotted or not--still exceeds yours. This means that simple non-sweetspotted f-airs or f-tilts or n-airs will outrange your standard shffl's. Your approach will be interrupted by his hits, because his range is better than yours.
Roy's d-tilt isn't meant to edgeguard (usually), it's meant to be used as a vertical launcher. It's probably one of Roy's best moves, because it's a relatively fast set-up for shffl'd u-air juggling on fastfallers, or f-air/n-air hits on everyone else.
Roy's recovery is pretty standard, actually. Like Marth's, side-b helps, but you can angle Roy's up-b to give better horizontal distance. Nothing great or nothing awful about Roy's recovery.
Additionally, Roy has a grab range equal (or almost equal) to Marth's. And as we all know, Marth's grab range is absolutely disgusting.
The reason why Roy loses this matchup is because Roy gets combo'd to hell and back. Really. Roy is quite possibly the easiest person to combo in this entire game for Mario. . .partly, it's because of Roy's perfect falling speed/weight (not to fastfall-y, not to floaty or heavy)--which means decent DI is a lot harder, but it's also because Roy seems to suffer from considerably more hitstun than everyone else. He gets caught up in that hitstun, and Mario can land hits faster than Roy can recover.
Even worse for Roy is that his shffl's are extremely vulnerable to proper crouch-cancelling. CCing makes Roy's aerials almost completely harmless, as the knockback on them--even when factoring in sweetspotting--is almost zilch. The stun time isn't that great either, so CC -> d-smash/grab/jab/--almost anything--will work moderately well against Roy.
Furthermore, as you said, Roy can't KO. At all. Anyone who can DI (which I hope all my fellow Mario players can by now
) can reduce the effectiveness of any of Roy's 'stronger' hits (neutral B, side-b combos, f-tilt, low-% f-smash hits, n-air). Roy essentially has to mindgame in his f-smash. . .which means that--HOLY CRAP--Mario actually beats the opponent in terms of KO power, and edgeguarding. Wow.
. . .again, I really don't think Mario ***** anyone, but if you had to classify matchups, this is as close to **** as it gets. If the person has decent mindgames (like NEO, anyone?), then Roy becomes friggin' scary as heck. But Mario definitely has the upper hand here.