Why is Pluto no longer considered a planet?

https://science.howstuffworks.com/pluto-planet.htm

Reason Why Pluto it is no longer considered a planet:

Size: It is smaller than Earth's moon

Composition: It is dense and rocky, like terrestrial planets. However, its closest neighbors are the Jovian gas planets. For this reason, many scientists believe that Pluto originated elsewhere in space and was trapped in the sun's gravity. Some astronomers once theorized that Pluto used to be one of Neptune's moons.

Erratic Orbit: The orbit of Pluto is erratic. Pluto, orbits the sun at an angle of 17 degrees with respect to this plane. In addition, its orbit is exceptionally elliptical and crosses the orbit of Neptune.

Size of its moon: One of its moons, Charon, is about half the size of Pluto. Some astronomers have recommended that the two objects be treated as a binary system instead of a planet and a satellite.


Opinion: 

Pluto does not have to be a planet because of the characteristics in which it fails, especially because of its erratic orbit, since it crosses Neptune, another reason is because of its size since its moon is almost the same size.