If a SMS share has “smart folders” disabled, the date taken into account is the modification date of the video file, even if it is inside a folder.
When “smart folders” is turned on, the date into account is, as it should, the modification date of the folder that contains the video.
This is in most cases a good proxy for the date the video was added.
This is also the date taken into account for OneDrives, even with “smart folders” turned off.
It certainly should be the same for SMB shares, smart folders being on or off.
