I was just glad to see there were no violent clashes between MAGAs and BLMs.

The crowds were smaller than expected. (Est: 6200) Trump hoped for a sold-out arena plus a massive overflow crowd. He and Pence were planning to speak to the overflow group outdoors in addition to the indoor arena crowd. Since the indoor arena had empty seats, there was no overflow crowd, so the outdoor speech was cancelled.

Pence’s portion of the indoor gathering probably could have been cancelled as well, given the crowd:

That pic was taken during Pence’s speech, but the arena still had plenty of available seats while Trump spoke. Example: