Just because Rust has safe guards for lock usage during unwinds doesn't mean it prevents all high level data structure inconsistencies or even just plain old bugs.

Doesn't matter how you choose to handle invalid semantic forms, either via undefined behavior, error code, exception, or assert, as long as you silently ignore it, your code is unsafe. Rust doesn't have undefined behavior but that doesn't mean it doesn't suffer from silent errors. E.g. Returning NaN from sqrt(-1) or signed integer overflow wrapping.

That's my entire point.

As a programmer your intent is to use APIs in the manner they expect. An invalid use is an invalid program. Garbage in, garbage out. No amount of subsequent error handling is going to help you. Better to abort().