You could, but my point is that it is easy to just slap things together using those engines, which usually results in similar feeling, low quality mechanics. Its easy to just use Input.GetAxis and apply some force for an asteroids clone, but now it doesnt feel unique. Thats what I’m trying to say. You dont have to use these, and you can make unique experiences with them. But the ease of access will also increase the amount of low to mid quality games out there, leading to people getting this feeling.