I get why most fans wouldn't like it if Street Fighter 6 switched to a simplified control scheme with less complex gameplay, but why not try it in a spin-off?

To this effect I'm not sure how familiar you are with SF but SFV simplified and streamlined MANY things that were in previous games. They heavily limited combos off lights, they got rid of proximity normals, they removed oki from throws (for the most part) and they homogenized the inputs quite a bit.

The result of this is the more hardcore players and fans tended to hate SFV (I honestly dont think its anywhere near as bad as it gets flak for) but it still failed to draw in new players.

I think at this point SF6 making inputs more simplified would probably kill whats left of the fanbase without drawing in new people.

I'm always open to new ideas. I'm not sure if you ever got a chance to play Rising Thunder but it was a fighting game that used 1 button inputs for things. so you had light, medium, heavy, special one, special two, special 3, throw and super.

It never really left technical alpha as the team was bought out by Riot to make a fighting game for them. We'll see what the fruits of that labor brings and how friendly to new players it is.