As someone who is traveling more domestically it annoys me when Y passengers come forward to use the F lavatory. We are specifically asked not to congregate at the galley so I wait my turn for the person to leave the restroom and the number of times someone comes up from Y before I have been able to get up from my seat means that often I will now stand in the aisle so I can use the F facilities. FWIW - I try not to use the plane facilities but when the flight is over a couple of hours my water intake results in the need. I really wish F FAs enforced the rule better in regard to Y passengers coming forward - I do understand the cart can cause a blockage for the Y passengers, but the Y passengers cause a blockage for the F passengers.

(I do not notice this issue on international flights as I think the FAs monitor this much better.)