Context: i am in Europe so might be irrelevant to US.
I was thinking : we already have a usable solution to traffic jams. It’s called parking lots, as the ones in airports. You drop your car, then you take public transport to go anywhere. So imagine doing the same, but on daily basis. Build many such parking spots outside of the city , irrigate with public transport, make the price reasonable for daily usage (fuck you Charles de Gaulle Airport and your 14€/day fee). Boom, reduces your traffic by X% every morning.
As someone who drives regularly from Reims to Paris, I d be glad if such option existed, so I wouldn’t have to drive on Périphérique.
The two reasons I think it’s not used is “planning” and “politicians”. The latter isn’t good at former.
I don’t drive in France, but there is already Train stations with parking, Centre d’expositions for example?
Park and ride require considerable space so often it might be preferable to park in a station that make the remaining journey okay or take the train directly.