I am not so sure that the "foreign student problem" is that simple. All kids have grown up in their own bubbles. Some will be more outward looking, others not. Wherever you come from. So there will be plenty who cling to the known, whether it is private school cliques, gf/bf, rugby team, or nationality group. And even for those who are interested in people from different backgrounds it can take time to identify common interests.
Some are lucky and make good friends through their flat, but others won't. Instead they may friends through their course, or societies. If the overseas students in a flat are hard working, clean and cook they cannot be that bad. The alternatives might be Young Ones stereo-types.
And overseas students can be pretty diverse. DS had a Chinese friend from Wales. Similarly a school friend of DDs has struggled. He is considered Chinese by the British students and British by the Chinese. A pity as he was genuinely popular and liked at school.
DS was one of only three British students in a group of nine when an undergraduate. They were pretty diverse and got along very well, with the social stuff mainly organised by kids from Hong Kong , Australia and Poland. DS was also nominated equal opportunities offer for one society because white English males were such a minority. Its serving him well on his Masters, as so far he has not met another English student, despite an intake of 39. The Europeans on his course think this is very odd, and DS seems to have achieved some sort of Ambassador status.
Early days, but University is the chance to meet people whose backgrounds are very different. Some overseas students will be dull and uninterested in meeting others, but so too will some British students. Coming from central London, DD initially saw the lack of diversity at her University as a potential problem, though it will be a chance to learn more about the UK. Her first placement is (rightly) in a very rural GPs practice.