Inaccurate error message when using parametric type recursion

Code

enum NestedDataType<T> {
    Nil,
    Cons(Box<NestedDataType<(T, T)>>),
}

Current output

error[E0392]: type parameter `T` is never used
 --> src/lib.rs:1:21
  |
1 | enum NestedDataType<T> {
  |                     ^ unused type parameter
  |
  = help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
  = help: if you intended `T` to be a const parameter, use `const T: /* Type */` instead

Desired output

Cannot support parametric type recursion

Rationale and extra context

No response

Other cases

No response

Rust Version

rustc 1.78.0-nightly (3406ada96 2024-02-21)
binary: rustc
commit-hash: 3406ada96f8e16e49e947a91db3eba0db45245fa
commit-date: 2024-02-21
host: x86_64-unknown-linux-gnu
release: 1.78.0-nightly
LLVM version: 18.1.0

Anything else?

No response

No repository files or tests are named. Reproduce the enum with rustc 1.78.0-nightly and compare the E0392 diagnostic with the requested parametric-recursion message. Trace the compiler path that reports the unused type parameter; done means the example emits the intended diagnostic without the misleading E0392 output.