So what?
"You cannot have anything because you will not get everything" has never been a strong argument. Should WAI 1.0 have been rejected because it did not cover every case?
I think there are three uses cases for named characters apart from so-called delimiter escaping:
1. The glyph is visually ambiguous. Such as nbsp. (The ZWNJ would be another.)
2. To indicate that a specialist character is involved, not the everyday one. A non trained user would not know which to pick. The MathML set has examples. outside of maths, tne dashes are another example.
3. in case the font does not have the glyph, or the user cannot figure out the name. Such as Euro, or Uuml.
I dont think the third reason has any traction this century. Nice to have, not must have. But nothing has changed for the second, and the first is an issue intrinsic to marking up text using text.
Cheers
Rick