The issue is not literal and the impact is not direct. Although Germany and France have been floated as other “banned/vetted” countries, I don’t believe it for a second. However, many applicants simply don’t want to apply to universities in a country where bigotry is seemingly condoned and/or where officially all their people have been considered dangerous. Once the brand damage has been done, actual policy may or may not follow through - mostly, the damage needs to be repaired.
Saudis may or may not be banned: it’s enough that the US would seriously consider it to impact the US brand abroad and redirect applications to other countries.
There CAN be a shift in where students apply based on a country’s image - and US influence is related to its image, in part. Students want to come because our universities are great and famous, but also for everything the US “projects” about itself. (Think of the US seen from abroad as a giant combination of the SAE incident if it’d taken place at Mizzou in the middle of last year’s problems. Think of the drop in applications that followed even if nothing was going on later on, that generous scholarships were in place, that Mizzou still has the best undergraduate journalism program in the US. There’ll likely be a little drop this year too, and then things will get back on track if nothing else happens at Mizzou involving ethnic slurs, racist moments, leadership failure, or protesting students.)
If official discourse becomes polite, restrained; if definite measures are taken showing care for religious and ethnic minorities; if the current incidents are condemned; if nothing bad happens in the net few weeks/months, then the anguish will abate.
The view that “something bad” is going to happen is widely-held enough that an airline made an ad that stated “Special prices: visit the US while you’re still allowed to!”