There are really three different downsides to this.
First, the foreign students cross-subsidize the locals' education. There are large fixed costs to running a university and these students pay way above their marginal costs. So now the universities have fewer resources; hence cutting the newspaper funding etc.
Second, the foreign students increase the schools' reputations and can collaborate with the faculty. Research is a public good. We do not have a research system so that we can think of things for nerds to do; we have it to produce valuable knowledge. In my own PhD program, the productivity of the Americans was much lower than the foreigners. That productivity led to discoveries that benefit everyone.
Third, immigration: some of the foreign students would have wound up staying. We should want these people to stay here and have families. Educated people who work hard and are ambitious enough to go overseas and stay are good for the country.
First, the foreign students cross-subsidize the locals' education. There are large fixed costs to running a university and these students pay way above their marginal costs. So now the universities have fewer resources; hence cutting the newspaper funding etc.
Second, the foreign students increase the schools' reputations and can collaborate with the faculty. Research is a public good. We do not have a research system so that we can think of things for nerds to do; we have it to produce valuable knowledge. In my own PhD program, the productivity of the Americans was much lower than the foreigners. That productivity led to discoveries that benefit everyone.
Third, immigration: some of the foreign students would have wound up staying. We should want these people to stay here and have families. Educated people who work hard and are ambitious enough to go overseas and stay are good for the country.