If you say so. But I keep everything charged, so I would never find myself with a dead phone while I'm waiting somewhere that I could layout a solar panel. OTOH the lack of convenient or available daylight hours could easily prevent keeping batteries charged.

Now if I go for days not riding my bicycle then you have a point. But only a catastrophic failure and the need to wait days for a part would cause that. And I'd probably have electrical outlets around in that case.

So I would maintain that for most people on a bicycle tour, the practical choice is dyno over solar. It's probably not just a matter of preference. Dyno has clear advantages.