That’s one of the reasons I ran the 2X4 along the bottom… I can attach a post with a swing down leg and adjustable foot to it. I hate to give up the quick access though. I made a little test table first out a sheet of mdf and when it sagged a single support in the center was able to completely flatten it out.
Honestly I thought the sag would be worse… according to the ‘sagulator’ calculator it should have been a 5mm dip in the center increasing 50% over time. Maybe it’s just pessimistic. I think a y plate and box 6” high would be much more rigid if someone were going for zero sag.
Adding up the specs on all the connectors I used they should be good for 6000 pounds and the weight of the table per stud should only be 35 pounds or so but again I’m no engineer I might have missed something.