Sure you could.
You could significantly lower the floor - or get rid of it entirely - and it would not effect how much money the players as a whole would receive.
The players are guaranteed their 54-57% (or whatever Players Share is agreed to in the next CBA) - no more, no less.
If the Lower Limit went away, some small market teams may spend less, but the only effect would be to reduce the amount that the Players would be giving back through escrow. In the unlikely event that total player compensation came in at less than the Players Share, the owners would have to make add'l prorated payments to the players to make up any shortfall.
