+1 on this.
Obsidian is pretty awesome, and it is frustrating to see this, I’ll use the word “rookie” mistake go unnonticed and untackled.
Filenames should not contain empty spaces, should be all lower caps, and English alphabet letters.
Even cyrilic alphabets can be transliterated automatically.
Duplicate filenames from stuff like “skola.md”, “škola.md”, “школа.md”, “Skola.md” - and similar can be fixed by adding a number at the end (WordPress automates this wonderfully with post URIs).
If there is fear of backwards compatibility, perhaps this can be set as a “core plugin” - letting the users enable it if they wish.
Problems I can see: first adoption, resolving stuff once the sanitization is enabled.
I think this is a must, and well worth it in the long run. May be missing something, but that’s my impression.
Relja