Universe errors involving an opaque type results in hallucinations and unused bound vars

Code (Rust ≥2018)

use std::future::Future;

fn main() {
    consume_async(async_fn);
}

async fn async_fn(_: &u32) {}

fn consume_async<F>(_: impl FnOnce(&u32) -> F) where F: Future<Output = ()> {}

Current output

error[E0308]: mismatched types
 --> ./t.rs:4:5
  |
4 |     consume_async(async_fn);
  |     ^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
  |
  = note: expected opaque type `impl for<'a> Future<Output = ()>`
             found opaque type `impl Future<Output = ()>`
  = help: consider `await`ing on both `Future`s
  = note: distinct uses of `impl Trait` result in different opaque types
note: the lifetime requirement is introduced here
 --> ./t.rs:9:45
  |
9 | fn consume_async<F>(_: impl FnOnce(&u32) -> F) where F: Future<Output = ()> {}
  |                                             ^

Desired output

error[E0308]: mismatched types
 --> ./t.rs:4:5
  |
4 |     consume_async(async_fn);
  |     ^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
  |
  = note: expected `_`
             found some type `for<'a> T<'a>` which implements `Future<Output = ()>`
note: the lifetime requirement is introduced here
 --> ./t.rs:9:45
  |
9 | fn consume_async<F>(_: impl FnOnce(&u32) -> F) where F: Future<Output = ()> {}
  |                                             ^

Rationale and extra context

It's very confusing to see a second opaque type and suggestions "to await both futures" (???, there is only one). Ideally we would properly note that the generic can't name the lifetime or something.

Other cases

No response

Rust Version

rustc 1.79.0-nightly (ef8b9dcf2 2024-04-24)
binary: rustc
commit-hash: ef8b9dcf23700f2e2265317611460d3a65c19eff
commit-date: 2024-04-24
host: x86_64-unknown-linux-gnu
release: 1.79.0-nightly
LLVM version: 18.1.4

Anything else?

#124471 has a simiular test case/issue but without the opaque types.

Reproduce the Rust ≥2018 example with the reported rustc 1.79.0-nightly version and compare the current and desired diagnostics. Investigate the compiler diagnostic path for opaque types and async futures; done means the misleading second opaque type and “awaiting both Futures” suggestion are removed while the lifetime requirement remains explained.