> people can only access Google Maps over proprietary channels where Google dictates the rules
WDYM? I use Firefox and I've never had a problem accessing Google Maps through it. Google controls the backend, sure, but I don't think they own any part of the "channel" I'm using to reach it.
Don't get me wrong, I like Osmand~ too; it's the only map app I have on my (gApps-free) phone. It's just not usable as a standalone navigation tool, so I typically have to rely on Google for at least part of the workflow.