How long do you think it will be before a non-European or South American (ok mostly Brazil and Argentina in modern football) team is a serious (and I mean genuine favourite, not underdog doing well like Morocco or Ghana) threat for the World Cup?
Who cares? It will be always the wealthier countries with the biggest financial packing and human resources. So, essentially more of the same.
But football as a business doesn't operate that. Evolving here isn't about bringing a contender to the World cup, that is an absolute narrow minded way to look at it.
Let's play it the opposite way in a more clear example. How long did it take anybody to challenge Americans in Basketball in the Olympics (only competition they take half seriously)? 1 time with no gold medal since they started putting professional in 1992, and that isn't going to end soon either. (And they put some awful roster in 2004 btw)
How many internationals in the NBA between now and then?
It was done to increase popularity of the game, to expand the talent pool.
Now the NBA is full of talents, some of them brought directly from Europe to USA, some brought directly from Africa, others were born and raised in USA, but most were brought abroad. Then you have local leagues and continental leagues developing in a much stronger pace, most of them now offer more money and more competition than G league. Even American players who declined or don't make it to the NBA benefits from it.
All of this because you gave the "poor Basketball countries " a chance to compete against the best.
Every aspect of the business, has evolved and developed into a much better game, only old heads are complaining.
It is the same and more in Football.
There are literally hundreds of leagues in the World, not just the 5 leagues we watch and CL. Every country has several tiers, cups etc.
When you give those countries that "Chance" you increase the popularity, increase the number of kids who wants to be footballers, increase the talent pool.
Guys like Mane, Salah, Khusanov were product of local academies. You think you would have watched those if this increased chances wasn't there? CAF helped many Nations in football when they give them ACN.
Again, every part of the business benefit from this on the long run. But old heads will always complain it isn't what they once used to.
To simplify it to "do you think someone can be a threat to the World Cup " is oversimplification and totally missing the point. The goal of the tournament isn't to find who has the best team, this is just part of what you consume.