People in North America don't realize how freeing it is not to have to own a car to do things but without adequate transportation they only see the inconvenience of not having one.
To an outsider (I lived in Grenoble before) it's so obvious that I joined some mobility associations as soon as I moved here, and I wasn't even politicized about this before, nor was I in any real sense active in the associative milieu.
So if you want to take a TGV to/from Paris, it is nice. Anything else, less so (try looking at fast train route from Lyon to Bordeaux - through Paris)
FWIW yes, TERs need much, much, much more love in France. Instead, the govt is still refusing to finance repairs to re-open e.g. the "massif central" line.
Would love to build a cool 'train arriving' system for my son to go up to the window and look at the train thats approaching
https://www.amtrak.com/track-your-train.html
The location updates, esp. in open areas, is a bit delayed probably due to poor cell tower access :-)
Here's a live one for Boston: https://tmap.live/
Here's a live one for NYC: https://aptransit.co/
Here's one for Amtrak: https://amtraker.com/map
For your son though just get the "Transit" app by CityMapper