Right now it's better in the USA and presumably easier to get funding for various R&D projects at post-grad level.
However your parent post was suggesting that this could extremely easily shift if it's hard for talented African/European/Asian students to get US visas, and China siezes the opportunity - investing heavily in R&D making student immigration easier.
Likely it won't change overnight, but it's not impossible to imagine a world where this scenario plays out - a few more Trump Executive Orders, a savvy couple moves from the CCP and you're not far off.
Another possible reality is that nobody benefits - the USA squeezes its intake of the worlds best and brightest, the EU is too busy puzzling over Brexit and similar distractions among South American, Asian and African nations (sorry I'm not familiar enough with their internal troubles to speculate) scupper their own efforts.
However your parent post was suggesting that this could extremely easily shift if it's hard for talented African/European/Asian students to get US visas, and China siezes the opportunity - investing heavily in R&D making student immigration easier.
Likely it won't change overnight, but it's not impossible to imagine a world where this scenario plays out - a few more Trump Executive Orders, a savvy couple moves from the CCP and you're not far off.
Another possible reality is that nobody benefits - the USA squeezes its intake of the worlds best and brightest, the EU is too busy puzzling over Brexit and similar distractions among South American, Asian and African nations (sorry I'm not familiar enough with their internal troubles to speculate) scupper their own efforts.