`unconstrained type parameter` with associated types that are actually constrained

I tried this code (playground):

pub trait Marker {}

pub trait Foo {
    type Bar;
}

struct Baz<T>(T);

impl<T> Foo for Baz<T> {
    type Bar = Baz<T>;
}

impl<T> Marker for <Baz<T> as Foo>::Bar {}

I expected to see this happen: successful compilation

Instead, this happened: compilation error:

error[E0207]: the type parameter `T` is not constrained by the impl trait, self type, or predicates
  --> src/main.rs:13:6
   |
13 | impl<T> Marker for <Baz<T> as Foo>::Bar {}
   |      ^ unconstrained type parameter

For more information about this error, try `rustc --explain E0207`.
error: could not compile `tmp` (bin "tmp") due to 1 previous error

And this confuses me, as clearly the T is being used in the associated type of Baz.

I searched around for other issues similar to this, but I couldn't find one matching exactly with this problem.

Meta

rustc --version --verbose:

rustc 1.88.0-nightly (092a284ba 2025-04-13)
binary: rustc
commit-hash: 092a284ba0421695f2032c947765429fd7095796
commit-date: 2025-04-13
host: x86_64-unknown-linux-gnu
release: 1.88.0-nightly
LLVM version: 20.1.2

Start by compiling the linked Rust playground reproduction with the reported nightly version and confirm the E0207 diagnostic. Investigate how unconstrained type parameters are checked when an associated type contains the parameter; done means the example compiles as expected or the intended behavior is covered by an appropriate compiler test.