This sort of transit just allows for further sub-urbanization and car culture when the highways fill up. It doesn't promote cross-sector density (just larger central business districts), and it doesn't reduce the externalities of the American way of living.
To be fair, this is by no means a mistake exclusive to red states. The WMATA in DC, and LIRR and Metro North in NYC all commit the same sin.
https://upload.wikimedia.org/wikipedia/commons/b/bc/Salt_Lak... Guess the mountains hem it in one some sides; that gives me some hope. Maybe someday it will look more like https://c1.staticflickr.com/1/659/32455034626_dc15a3023b_o.j...
It should also be noted that Calgary faced similar challenges to SLC, and they optimized for it in similar ways: optimizing for total system length and highest frequencies per dollar spent, and often developing suburban park and ride stations. And over the last 40 years, Calgary has become more dense as a result. It has become one of the highest ridership per mile systems in north america, better than any in the US, besting even a 125 year old line with significant subterranean sections right through the dense core of Boston.
I will hand it to Calgary though. Reading around, it does look like the job density is in the central business district is exceptionally good for such a late-developed North American city. The park and rides don't dent housing sprawl at all, but at least they allow people to commute to the same place. Hopefully that does create demand for dense housing around the central business district eventually.
I think at this point we also need to massively raise the gas tax, pay it back as a universal dividend to avoid right-wing revolution. And simultaneously, we need to build a bunch of transit so people trying to win the gas-tax-dividend arbitrage have a valid strategy. Make the demand, make the supply.
Our political situation doesn't allow for that, but I don't really see the choice? Trying to electrify all the cars is perhaps easier on the American psyche, but much less efficient, and will not help with all the non-global-warming major externalities we need to fix nearly as urgently.
This is perfectly exemplified by UTA Trax, which had a humble start in slightly blue SLC, but has expanded outward at an incredibly rapid pace, with approval votes coming from some of the reddest counties in the nation. Building efficiently and cost effectively is quite possibly the best vote-switcher on transit that we could make.