When I graduated in 1990 we didn’t wear swords. I think it is common practice for the graduating class to not wear swords. Can’t remember if the officials on the reviewing stand were wearing them or not.
I went to a military high school and we (at least the officers) did wear swords, even when big shots came to review our parades. We all got called out onto the football field in the middle of the night once becaue Nixon was supposed to make a visit... but it got cancelled after we were all assembled. Perhaps he heard there might be swords present!