Event Category required

I am trying to make event categories a required field. I have found the documentation on the Modern Tribe site of how to do this however I am wondering is there a different way than using the code ‘tax_input’ – If the person forgets to fill this out then the error message says Tax Input required. This says nothing about event categories even though this is the field for this selection?

While it works adding in the code it doesn’t make any sense for users and ends up causing more questions then why their event didn’t show up on the calendar.

Is there a way to make this event categories or change the required message it gives?