I think the main reason for FIFA to let three countries host the world cup instead of one country is that we are going to have more national teas in the world cup and more teams need more sports facilities and need more potential from the host of the world cup, that's why we are going to have three countries hosting the 2026 world up instead of only one.
USA and Canada teams are not the famous teams in FIFA - but that too is true USA and Canada will be host the tournament very well.