>>717064362They're just fighting games, but with a different skill set: neutral is different, movement is more important, and advantage and disadvantage are more flexible. You need to actively restrict your opponent's options in a 2D space where they have much more freedom of movement. A lot of 2D fighting game players who pick up platform fighters play in a very particular way that demonstrates this difference. Just watch Sajam try to play Rivals 2.
They are easy to get into because the barriers to entry are less daunting to people who don't have prior experience with fighting games. Simply controlling a character in platform fighter space - making him walk, run, jump, and do different attacks - is easier to grasp than learning and practicing the concepts you need to do well in traditional fighting games. Sure you can play Street Fighter by finding good buttons and pressing them, but you're going to get washed by anyone with an ounce of fundamentals. Both subgenres are difficult to master though.
