It's not that I can't see your reasoning for the suggestion, it's that I think other things (not forcing one demographics' preferences upon others, mainly) matter slightly more. I can certainly see your point. However, someone might want to change route mid-drive, or maybe change some settings, or whatever. Alternatively, 'forcing a touch' to ideally pull/stop a car/bike over to make changes/adjustments is a normative claim - I.E. that it's a good thing to force people to do that. At any rate, I agree with you that that's something that would convenience a bunch of people - however, I do NOT think that it should be the automatic hard-coded thing, that pressing a Voice Guidance Icon should also full-screen the program - it's fine as an option, even as the set-on-by-default behavior, but I think that if implemented, it should be disable-able through some settings menu. Alternatively, simply having a full-screen button should suffice, honestly.