Does she spot problematic patterns more among people who have poor English than those who have fluent English? I’m sure your mum is lovely, really I do not mean any disrespect, but I really suspect that subconscious bias may be playing a major role, here - it’s easy for out-groups to stand out and to see a pattern which isn’t really there - it’s just how our brains function.

In the full interests of fairness, I also do know that some people who speak ESL do sometimes weaponize their issues with English if they think it could benefit them, e.g. pretending not to understand something they actually do. In their defense I would probably do the same thing if I could get away with it tbh