If Pluto has not cleared its neighborhood of objects in its orbit then neither has Neptune since Pluto crosses its orbit Why is Neptune not excluded from the list of planets?

Answer 1

It crosses another planet's orbital path. Since Pluto is not a planet, it does not matter. Comets always pass other planets' orbital paths. They are still called planets. Countless asteriods and comets orbits the sun and crosses every planets orbital path. Pluto is somewhat a part of them.

There is something circular about the logic in the above answer; see discussion.

Probably a stronger answer is the fact that even though a section of the orbit of Pluto comes within the orbit of Neptune, the harmonic relationship between the two bodies is such that they can never collide, barring some catastrophic event that alters one or both orbits. Neptune and Pluto are locked in this harmonic relationship where for every three orbits of Neptune there is exactly two orbits of Pluto. So Pluto cannot be seen as an object that Neptune must clear. Pluto is more like an unusual moon of Neptune.

Answer 2

Neptune has a dominant gravitational influence in its orbit, and there are no other objects of comparable mass in its vicinity. While Pluto's orbit crosses Neptune's, Neptune is much larger and has a stronger gravitational pull, making it a clear dominant body in its orbit. This is why Neptune is considered a planet while Pluto is classified as a dwarf planet.