I agree that rejecting valid non-Latin characters in valid contexts is user-hostile, but I should be clearer about scope: this is specifically about machine-readable identifiers (slugs, handles, ENS names) where the character set is intentionally restricted, not display names or user-facing text.

The approach there should be what wongarsu describes below (imo), to style the UI so official accounts are visually distinct (badges, colour, etc.) rather than policing the character set.

namespace-guard is deliberately opinionated for the slug/handle case where you've already decided the output should be ASCII-safe. If your use case is broader than that, confusables detection without rejection is the right call.