iOS at least renders it as an n with dieresis; is that how it was intended (I’m unfamiliar with musical notation)? If so, what is so difficult about it?
In fact, (semantics aside, from a technical perspective) the preference should always be for modifiers rather than standalone characters because the chances of being supported by the viewer’s font are much greater: it doesn’t need a separate glyph explicitly drawn and add to the font file for the code point. Difficulties in entering it or typing it out should be mitigated with client-side affordances in the UI, shortcuts, etc.
In fact, (semantics aside, from a technical perspective) the preference should always be for modifiers rather than standalone characters because the chances of being supported by the viewer’s font are much greater: it doesn’t need a separate glyph explicitly drawn and add to the font file for the code point. Difficulties in entering it or typing it out should be mitigated with client-side affordances in the UI, shortcuts, etc.