I was wondering about that…
Yesterday I arrived in Basel from France, and the TER was delayed so I only had 5 minutes to get to my next train. As I am a brisk walker and know my way around the station I still made it, but just barely.
I know that with a supersaver ticket you can treat a connection as “missed” if a delay reduces the connection time to below the minimum for that station. I suspect that Basel SNCF -> Basel SBB is at least 10 minutes, but would be interested in a confirmation.