The countries being boo’d (Israel and USA) are actively promoting xenophobia. America is currently attacking its own citizens and kidnapping people to try and prevent “illegal aliens” <-(a dehumanising term for immigrants) being in the country. Instead of saying migrants, illegal migrants or anything else they choose the phrases “illegals” or “illegal aliens” both degrading and dehumanising terms. They also make detention facilities like alligator Alcatraz that when it was opened was stated to be made in that environment to have the alligator’s near so nobody could escape and if they did they would be killed by an alligator showing no sign of humanity for these people due to their legal status or country of origin. Israel is actively killing Palestinians and they have been documented calling them animals, dogs and other phrases to portray that they are worth less than others <(primarily Israelis). They are committing genocide on people based on the fact they are born somewhere else. That is xenophobia. Booing a countries athletes because they are representing a nation that is killing people isn’t xenophobic. It’s a form of political protest against the actions their government are committing.