Because unlike the original it's not a "show for girls in kindergarten". It was created by Lauren Faust who has worked on other popular kids shows like power puff girls and fosters home for imaginary friends.

People generally like it because not only is it cute and wholesome but its actually pretty funny, well written, and has a lot of adult jokes and references such as from Rick and Morty, doctor who, the big lewbewski, Hitchhikers guide to the galaxy, dungeons and dragons, they even did a really great subplot about the dangers of communism.

The reason it gets a lot of hate is because people compare it to the original or the toys without watching a single episode, I would probably compare the quality to other shows like Spongebob Squarepants and Fairly Odd Parents.