The default Illustrator underline is a brute. It is a single, thin stroke anchored to the font’s baseline. It doesn't care about descenders (the tails on 'g', 'j', 'p', 'q', or 'y'). It slices right through them like a laser through fog. For a legal document, this is fine. For a luxury logotype or an editorial headline? It’s typographic vandalism.
Welcome to the secret weapon of the Illustrator power user: . illustrator underline
But Adobe Illustrator is not Microsoft Word. It is a precision machine. And within that machine, the humble "Illustrator Underline" is not a single tool, but a philosophical fork in the road. Do you let the software decide where the line goes, or do you wrestle control for yourself? The default Illustrator underline is a brute