Indeed, the US has a major lack of fixed-line competition and lack of regulation. Starlink doesn’t really help with that, at least in urban areas.
I’m not familiar with the wireless situation. You’re saying that there are significant coverage discrepancies to the point where many if not most consumers are choosing a carrier based on coverage, not pricing/plans? There’s always areas with unequal coverage but I didn’t think they were that common.
Here in NZ, the state funding for very rural 4G broadband (Rural Broadband Initiative 2 / RBI-2) went to the Rural Connectivity Group, setting up sites used and owned equally by all three providers, to reduce costs where capacity isn’t the constraint.