That’s a very good argument you have, other clever minds like you have thought the same. I once saw someone argue that Jupiter, the largest planet, technically hasn’t cleared it’s orbit because of the Trojan asteroids. Earth hasn’t cleared it’s orbit because of 3753 Cruithne. But they made an exception for objects that a planet can never collide with due to orbital resonance.
However, if you are arguing that there are small bodies that Earth can collide with out there, then you are correct. There is, but you have to understand that Earth’s mass is far greater than all of the near-Earth objects combined. Pluto, however, is not greater than the mass of all its near-orbit objects.
Your argument is strong, but sadly a lot of factors play in that doesn’t make it a easy matter. For now, under current rules, Pluto is not a planet.