Just for posterity's sake, I wanted to highlight the lilypond-user listserv response to OP's question when they asked it there. (You can find the thread here.)
SMuFL support would not change input syntax. It is about allowing the
use of many alternative music notation fonts that follow this
There was a blog post on Scores of Beauty explaining the ...
Not a complete answer to your question for reasons mentioned below, but you could start by doing a few experiments to find out why it is in your case that sung notes don't trigger the automatic verbal associations (note names) which appear in your conscience like when you hear a piano note or other instrument.
You could, for example, take some recordings of ...