I think this makes the situation much more complex that it really should be. As I mentioned previously in this thread, the "true" P.Type kinda already exists, but it's not obtainable or properly expressible. This metatype fix via the any keyword allows us to also fill this hole.
protocol P {}
func whatAmI<T>(_ t: T.Type) {
print(type(of: t))
}
whatAmI(P.Type.self) // P.Type.Protocol
^~~~~~
Make a breaking change, and let P.self actually return that P.Type instead while shift the previous P.Protocol to be the result of (any P).self and re-brand it as (any P).Type. Done.
People are constantly reaching out for P.Type but get (any P).Type instead because of all this metatype fusion madness. This is the right time to fix this, and I disagree that it's orthogonal to this proposal. Having the ability to actually get the singleton metatype P.Type would fix sooo many issues and confusion in the swift community.
This one extra thing unlocks an entire new set of generic algorithms. We can either ignore that or push this forward while we're already changing the status quo here. I've earned a lot of disagreement in this thread, just to see the core team join the conversation and make things clear to actually include the changes I've been fighting for the whole time.
P.S.: If you have Swift compiler know-hows, implement a quick and dirty proof-of-concept of this and see how awesome the expressiveness of the language becomes. It's a win win situation.