As others have said, much better to leave it open (after testing that it will close if you have any doubt) so others can fit smaller items in, or if anything can be rearranged (bags not tightly packed, put in sideways when they could be wheels in, or horizontally in the newest bins that can fit bags vertically).
If I'm an FA (I'm not) I actually want to push them closed myself so I'm sure they're all latched properly.