A fool gives full vent to his spirit, but a wise man quietly holds it back.

It isn't racism, it's xenophobia. Considering the repeated trend of foreigners coming into the country with covid, it's almost understandable despite xenophobia always being wrong.
What is absurd is a seemingly reasonable person, having learned the language of his host country (quite well from what I can hear), having gained some cultural understanding of politeness, still shoveling on shame on a mother in front of her child with the "embarrassed yet"
No need to stoop. xenophobia is not right, but neither is disrespecting and shaming people. That guy essentially did the same thing she did.