Why does google insist on using the name of the letter for voice to text?

It knows my phone has a keyboard. It makes a big difference for me to say something like "capital n" or "shift" instead of saying the full name of the letter. For example, to spell out my username I would say: "i, p, capital i, capital s, shift for caps lock, 1, shift, capital e, capital d, shift, capital a, capital b, capital o, capital u, capital t, space, a, capital s, capital i, capital e, capital n, capital c, capital e, capital e" and that is a lot easier than "I, pee, eye, es, eye, ex, one, eye, eye, pee, eye, eee dee ee, eye, bee out, ay, ay, es, eye, eye, eye, ee, en, see, ee" <br>If I am using voice to text then I have no keyboard access, so why do I need to identify the keys? Why does Google think I am accessing voice to text on a desktop?