The most obvious main difference is the general rule of women preferring cuter stuff to men’s cooler tastes
There are obvious exceptions, god knows /vp/ is full of them and I’ve seen a huge amount of men who are cute-design enjoyers as opposed to more fond of cool things, but that’s a good starting point.
It can also be rephrased as “monsters vs plushies”, “friends vs predators”, anything like that. The gnarlier the design the more men are going to appreciate it over women.
This leads to a lot of women preferring unevolved forms for their cuter appeal, a lot of men preferring full evolutions for their intimidation factor, and a similar effect applying to typings (“scarier” typings like poison and dragon have more male fans than “cuter” typings like grass and fairy).
Honestly, though, this is mostly useful with casual fans as opposed to hardcores. Hardcores are too autistic to follow patterns and tend to like their own things for their own reasons.