For a country where most people pay $50+ per month for 4G, this coverage really is pretty poor. There are tens-of-mile wide gaps in coverage.
Now Norway is the size of about the California and probably easier to cover one could say but the population far less and I can’t imagine what the telcos bring in per user which doesn’t even even go towards their infrastructure.
US mobile and internet cover is crap and will need regulatory intervention if we want to get it in rural areas IMO.