My #2 son's girlfriend is Chinese, here doing a PhD (waste management). He works in finance (BSc&MSc), has just visited China and loved it. I guess this sort of thing will result in both of them leaving the UK for China, taking away two high-paid, motivated and highly-educated young people.
This announcement is performative crap, continuing the anti-foreigner rhetoric of this govt as it chases voters who will never vote for them. International students know about visas, know what'll happen. This from the government is unnecessary for them, so it's clearly just red meat for the racists.