Thought this link may be of interest to someone (yes, I'm a bit of a long-time admirer of the bikes on that site). Basically suggests using a German train app to plan French train journeys. I have no experience of this, but perhaps it is of help to someone.
They do say there are some that take bikes "There are a few with a bike compartment which have room for 5 bikes but they are as hard to find as the proverbial needle in the haystack."
Pointing out which TGV lines take full bikes would be useful.
Thought this link may be of interest to someone (yes, I'm a bit of a long-time admirer of the bikes on that site). Basically suggests using a German train app to plan French train journeys. I have no experience of this, but perhaps it is of help to someone.
https://www.lafraisecycles.com/news/2022/4/28/traveling-by-train-and-bicycle-in-france-how-its-done-no-you-dont-have-to-take-your-bike-apart