No, it's not true.
Over the last six years, I have made so many friends and lived in houseshares with dozens of international students from all over the world.
America, Bangladesh, Canada, Greece, India, Iran, Jordan, Libya, Mexico, Norway, Qatar, Sierra Leone, South Korea, Thailand, Turkey and Zimbabwe.
So many friends from uni come to visit me whenever they are in London, invite me to stay with them and send me birthday & Christmas gifts every year.
Some people can be cliquey and only willing to talk to old school friends or coworkers.
But they won't join uni student societies, avoid all social events and usually hurry in&out of uni as fast as they can.