There was previously another post demonstrating a way to bypass trait bounds. That one was a bit too unreadable. Here’s my take on it.

trait Super {
    type Assoc;
}

trait Sub: Super<Assoc: std::fmt::Debug> {}

fn do_debug<O: Sub + ?Sized>(x: O::Assoc) {
    println!("{x:?}");
}

// Doesn't need T: Debug
// Debug-prints the value of x.
// Works even in generic contexts where we don't have a T: Debug bound.
fn debug<T>(x: T) {
    do_debug::<dyn Sub<Assoc = T>>(x);
}

fn main() {
    debug("lol");
    debug(123);
}

(playground)

Based on: Associated type bound from supertrait isn't checked for trait object · Issue #152607 · rust-lang/rust · GitHub

Obviously don’t use this in production lol

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