Ideally that lint would be on by default though. Most code doesn't use non-ASCII identifiers. It's not happened though because of uhm. political reasons.
Most code made by English speakers contains English word and Latin characters, so other languages and alphabets must be abandoned, and their native speakers must imprisoned until they understand their mistakes.
Abugidas and logographies banished
OK, OK, we can start with a warning in the compiler that use of any language except English is unsafe.
The lint is on by default in the latest version of the compiler