I personally have no trouble playing Roy, and having no safe way to KO an opponent is not true, Up-B out of shield is a great kill setup because of its super armor and fast start up. Roys F-Tilt is also really fast and can kill, same with Fair. That's just his safest ones.
Ok ok, but have you played Roy before in a tournament situation where players won't be able to abuse FD and input lag? Just a curious question. Roy online is far better online where it's harder to react, giving the impression he can KO reliably. Also, no stage other than FD in my opinion helps Roy, as platforms just make it far easier to combo Roy due to his high fall speed.
Regarding Roy's recovery, it can be angled slightly, but that's just the move. Recovery consists of multiple things, such as distance and fall speeds. Roy's fall speed is very high, and this hinders his recovery. The moment Roy gets hit off stage, his high fall speed can haunt him. His recovery move is also relatively slow. When comparing it to Marth for example, Marth has a slower fall speed, a far quicker recovery move, making it safer off stage, and it also reaches slightly higher too. More often times, Marth can recover on occasions Roy cannot. Of note, Roy's Up B has more landing lag than Marth's too, making it far more unsafe if missed, and in general, less safe as an OoS move. It is rather strong though, so that's nice.
And another thing. While things like Ftilt and such are strong and relatively fast for killing, you must always remember that they only do so when sweetspotted, and you must consider the sweetspot placement, which is close to Roy. This means, that while Roy has disjointed range, he must fight up close like a brawler to be able to KO or score consistent damage. This completely mitigates the point of him using a sword, which can be used to strike from a distance and or use to defend, which Roy cannot due to the sweetspot placement.
And it's the sweetspot placement that harms his other moves and kill setups. Falling Up Air works pretty nicely, but it is very shaky and unsafe, as for it to work, you must hit a grounded opponent, so you'd need to use the side hitboxes and hit the sweetspot. If missed, or sourspotted, this sets Roy up for an opening for punishment.
I don't think I have seen anyone ever mention his neutral special as a serious kill move. Yes, it has little endlag, but it's relatively weak unless charged. It's far better as a baiting move to see what your opponent likes to do, as the endlag is rather quick.
That's the thing with Roy, he relies too much on baits and mistakes from the opponent. He has no real combos, as DI prevents almost all true combos at low percents. He has no real safe way to approach the opponent due to lack of autocancels. He struggles to KO safely due to lack of poor approach, KO confirms, and laggy, high commitment smashes. He cannot space or play defensively very well, or at all, due to his sweetspot placement. He has a poor off stage precence, despite his sweetspotted aerials power, due to a combination of high fall speed and a sub par recovery move, meaning he can't go deep for long, or in some cases, at all. He is also combo fodder for most characters due to his high fall speed and mid weight. Roy also lacks noteworthy results overall. Combine all this together, and you have most certainly, a character that is not above low tier.
Don't get me wrong, I myself do think Roy is slightly lower than he could be, but it's not something we can solidly prove, because he lacks representation and results. I wouldn't put Roy any higher than low tier however. Roy isn't a bad character so to speak. Remember, bad in this game is no where near the same level as bad in other games.