In what way? It doesn't physically spin (hasn't for years), so there's no issue of that. The wheel itself is just touch sensitive, and if it bends
slightly to conform to the face of the thing (we're not talking anything huge or ridiculous, if the above photo is anything to go by...it looks fairly flat to me), I don't see how it's a problem.
Or were you talking about some other aspect (no good side grip or something)?
If the above pic is legit (I can't tell, but it's a pretty nice mockup if it's fake), then apparently Apple doesn't have - or see - a problem with it and they've manufactured the thing.