We had this discussion so many times. My suggestion is to have at least 6 slots for the CONMEBOL confederation instead of the current 4.5. Teams such as Qatar, Saudi Arabia, Tunisia and Cameroon will be participating in this edition of the world cup, while strong teams such as Colombia and Chile are unable to secure their qualifications. Now please tell me one thing. Are teams such as Colombia inferior to AFC teams such as Saudi Arabia? Even the lowest ranked CONMEBOL team (Bolivia) plays much better than Saudi Arabia.
But it's also a matter of diversity. The World Cup would be much less appealing if there were 90% European and South American teams only. But I agree that this would be an interesring format if we had a worldwide qualification somehow to guarantee that are only the best teams qualify for the tournament. Maybe the FIFA could have a one time special event (outside of the regular world cup), like the European Nations League (but it should be more appealing that the teams actually care 
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