I agree, this is a good use of the live service model to improve the gameplay experience. Previous entries in the Flight Simulator series did have people purchase and download static map data for selected regions, and it was a real pain in the butt – and expensive, too. Even with FS2020 there is a burgeoning market for airport and scenery packs that have more detail and verisimilitude than Asobo’s (admittedly still pretty good) approach of augmenting aerial and satellite imagery with AI can provide.
Bottom line, though, simulator hobbyists have a much different sense of what kind of costs are reasonable for their games. If you’re already several grand deep on your sim rig, a couple hundred for more RAM or a few bucks a month for scenery updates isn’t any big deal to you.
FWIW there is a cottage industry for OnStar disable/delete mods for GM vehicles. It can be done, usually without breaking too much else of the car’s electronic functionality.