Odd thing to care about but it shapes how you play. V had autosaves at mission boundaries plus manual saves at safehouses. RDR2 had a more restrictive system that annoyed a lot of people.
With chapters mentioned and safehouses being more involved this time, I would expect a save system closer to RDR2's. Has anything been said, or is this another unknown?
Nothing said. Chapters being mentioned is the only structural hint and it points the way you are pointing, but it is an inference from a single word.
coming back to a character exactly where you left them three days ago is the funniest thing about switching in v and i hope they kept it
RDR2's save system annoyed people because manual saves were awkward, not because autosaves were rare. If they fix the interface nobody will complain about the structure.
With two protagonists there is also a question of whether saving parks the other one somewhere sensible or whether you come back to Jason standing in the sea.
That is a useful distinction and it is probably what actually happened. People said save system when they meant menu.