https://www.youtube.com/watch?v=wk0lRmduxSI
The image you posted IS the rear group of a few selected people for Biden. The main “crowd” is on the other side of the stage. The crowd starts at about the middle of the high school(?) basketball court. They never show the far end of the crowd, but even if it extended to the far wall it wasn’t that many folks.
Or just listen to the comparison between the crowd noise.
Pathetic “crowd” for a sitting President which only lends credence to Joe’s Resident status.