It has been many years now that France has limited Eurail/Interail access on TGVs. TGVs require a reservation. Unless you can plan way ahead--which defeats much of the beauty of the Eurail--it is often cheaper to buy tickets online than to use a pass. Not only do you have to get your reservation, too, which increases the cost of each individual trip, but the SNCF limits the number of Eurail-pass-holder seats quite a bit. As a result, I have been caught more than once holding a pass but having to buy a regular internet ticket when I wanted to take a train 6 or 7 days out (not knowing when I would want to travel in advance).
This is exacerbated by the fact that France has, for over 10 years now, poured resources into money-making TGVs at the expense of slower regional trains. Sometimes it is impossible to avoid a TGV or at least extremely difficult to travel by train other than TGV or a night train (which requires also getting a couchette, another expense and you don’t get to see the countryside). Marseille-Paris, for example.
Travel in countries further to the east also often requite a reservation, but they are much easier to obtain (Germany, Austria, Poland, Slovakia, Switzerland, etc.).
Are there any workarounds here? Any chance that Eurail will negotiate some new initiatives with the SNCF to make “spontaneous” travel in France more pass-friendly and therefore more affordable?