I think the problem here is that we need to establish there is a significant difference between "camping" and "zoning."
@
speedguy20
You mentioned other people complaining they're being "zoned out" by Megaman. "Zoning" =\= "Camping"
When people talk about "zoning" they usually mean keeping within a very specific distance from a character. With Megaman, that distance is usually the maximum range his pellets can travel. It takes a certain amount of skill to constantly keep an opponent within that distance while both players maneuver back and forth across the stage.
It certainly takes a lot more effort than "camping" which is basically standing on one edge of the stage and firing the same few projectiles as a method of winning. This type of "camping" can't even be done by Megaman effectively, considering how much lag there is between his Pellets/B special moves, how easily they can be defended against, and probably most importantly, how little knockback these moves have.
Projectile camping can be so effective because the projectile in question usually have a significant knockback to them. Lucario's Aura Spheres, Samus' missiles and Neutral B, Link's arrows/boomerangs, all of these moves push the opponent back at mid-high percents, in addition to having little ending lag so they can quickly charge up while the opponent was pushed away by their previous projectile and throw another projectile.
The only projectiles with knockback that Megaman has is Crashbomb and Forward Smash. Crash Bomb is nearly impossible to projectile spam with because:
1. It must attach to the opponent successfully. (It's not too difficult to protect oneself against)
2. It must detonate successfully (and there's many ways to protect oneself against an attached crash bomb).
3. Only one Crash Bomb can be fired at a time.
4. There is pretty good ending lag between this and the next special button input.
Forward Smash cannot be spammed because of it's huge ending lag, which if whiffed, will receive heavy punishment.
Metal Blade is probably the one move that can be 'spammed' but even then, the opponent has ways to prevent this by catching it out of mid-air and holding onto it. And just like crash bomb, there can only be one out at a time.
Pellets can also be "spammed" but they only have one trajectory: straight ahead. They also disappear about 3 character lengths away and don't have much knockback at all, unless it's nair's sweetspot.
This means that an opponent can take a more vertical aerial approach towards a Megaman who consistently uses pellets and get in this way. Some can even just push through the lemons and get to Megaman anyways.
TL;DR
None of Megaman's projectile moves have the characteristics that let Megaman stay on the edge and spam. Camping on the edge will almost definitely not win Megaman the match.
Any Megaman must skillfully zone a certain distance away from the opponent during most of the match if they want a solid chance at winning, and this takes far more skill than camping at the edge.