I have many projects that I work on and the Date Modified is always wrong. For example, I may work on a project today, and tomorrow it will say that the last Date Modified was 5 months ago. The friend I work with has the same issue, has nobody else had this issue? It's been like this in both Unity Hub 2 and 3. I'm in the UK timezone so figured maybe the devs are sorting date time by USA time format. It's super frustrating.
it seems to check last modified date from the project root folder (mtime), can you check in windows explorer, what it displays for Date Modified? it should match what hub displays.
yes, for me the folder date instantly changes, even if just open the project (and don't change anything). (i'm on pc, win10)