FWIW I don't think panics are a bad idea necessarily, they're just very different from errors. Errors are part of the API contract (whether enforced by the language or not). Panics are for when the contract is broken on either side, or expected invariants suddenly don't hold - the reason being that if your basic guarantees about process state are broken, you can't really guarantee that you'll be able to handle the error either, and trying to do so regardless might result in a security issue.

This distinction is growing popular in general, including languages that have exceptions (e.g. FailFast in C#) and error types (e.g. panic in Rust).