Rationale behind excluding some unicode characters from identifiers

[t-bltg]

I’ve opened [FR] Allow more Unicode characters from `Ps` and `Pe` categories for identifiers · Issue #48885 · JuliaLang/julia · GitHub and Allow more Unicode characters from `Ps` and `Pe` categories for identifiers by t-bltg · Pull Request #48886 · JuliaLang/julia · GitHub, to be discussed.