rustc confuses missing types with missing type parameters

Code

pub fn do_stuff() -> Option<ForgotToImport> {
    None
}

Current output

error[E0412]: cannot find type `ForgotToImport` in this scope
 --> src/lib.rs:1:29
  |
1 | pub fn do_stuff() -> Option<ForgotToImport> {
  |                             ^^^^^^^^^^^^^^ not found in this scope
  |
help: you might be missing a type parameter
  |
1 | pub fn do_stuff<ForgotToImport>() -> Option<ForgotToImport> {
  |                ++++++++++++++++

Desired output

error[E0412]: cannot find type `ForgotToImport` in this scope
 --> src/lib.rs:1:29
  |
1 | pub fn do_stuff() -> Option<ForgotToImport> {
  |                             ^^^^^^^^^^^^^^ not found in this scope

Rationale and extra context

Type parameters are rarely this long, so rustc's guess seems like a poor fit. Could rustc treat longer names as unlikely to be type parameters?

Another option would be to skip this suggestion if the type name is CamelCase.

Other cases

Rust Version

$ rustc --version --verbose
rustc 1.86.0 (05f9846f8 2025-03-31)
binary: rustc
commit-hash: 05f9846f893b09a1be1fc8560e33fc3c815cfecb
commit-date: 2025-03-31
host: x86_64-unknown-linux-gnu
release: 1.86.0
LLVM version: 19.1.7

Anything else?

No response

Reproduce the diagnostic from the src/lib.rs example using rustc 1.86.0 and compare the current output with the requested output. Review the compiler diagnostic path that proposes a missing type parameter, then determine which agreed rule should suppress the suggestion for this case. Done means the unwanted help text is absent while valid missing-type-parameter suggestions remain covered by tests.