"Obligated" is a strong term. But if I think the players have forgotten something that their PCs would have remembered, I remind them - things that happened a week ago for the PCs could be several months for the players, and the PCs are possibly smarter and definitely more motivated than the players. If something is borderline, I might ask for an Int or Wis check (whichever is better for each character) to prompt the reminder. Well, if something is borderline I'd probably still just tell them, but if something is borderline of being borderline I'll call for the check.
Assuming of course I remember, which is by no means a given for the reasons mentioned above.
(Given which forum we are in, I should mention that I mostly run PF1 and PF2 these days and have never actually run 5e, but if I were to do so I doubt it would change anything about the above except possibly the DC of the check if one were required.)
EDIT: Sorry for the necro. Not sure how I ended up reading a thread from August without realising it,