Ehhhh yes and no...
CONCACAF yes. Mexico looks very good this year. Against Germany they were organised, they were fast, physical, and their defense was solid. Costa Rica made it to quarterfinals and didn't get blown out when they lost in 2014. Team USA was in quarterfinals in 2002. Its just USA's team is going through a bit of transition at the moment.
Asia, no. Definitely no. There's still a huge gap between Asian teams and European & South American teams. Japan is probably the best one they've got. Now credit to them for forcing Colombia into a corner early and making them err. But one has to wonder how Japan would have fared against an 11 man Colombia. Japan actually seemed to struggle in much of the game against 10 men. Iran put up a valiant defensive front against Spain, but didn't know how to attack them it seemed. When they broke their defense, they were not very organised in doing so (offside on their best shot at goal) otherwise didn't do much with the ball when they had it. These are Asia's best two and they still struggle to close the gap.
Africa is odd. They have only a handful of teams who can do it but they have shown the potential to make the distance. Much of the continent has a plethora of issues preventing the production of high-skill football. Most of those countries are very poor so not only do they struggle to get the nutrition for their children to grow up to be faster and stronger but they also lack the facilities and training programs that they have in places like Europe or South America.
Lest we forget Nigeria won the 1996 Olympic Tournament, the first of their kind. Nigeria has been a little on-again-off-again year to year. This year doesn't look like their time as they're the youngest team by average in the tournament. To win the WC you need plenty of experience. Senegal surprised the world in 2002, and that was their 1st appearance. And one player from that team became their coach. They probably have the strongest chance (seeing they're the only African team who has won so far and with relative ease no less). Ghana could have made it to the final in 2010 if it weren't for a missed penalty that Suarez gifted them at the end of extra time. And could've made a splash in 2014 as well if it wasn't for the players getting greedy and getting impatient over the money they were expecting to earn just for showing up. I'm afraid Ghana's time has passed for this era. Ivory Coast & Camaroon are examples of other pretty-good African teams.
I can see where you're coming from saying that we can see it happening soon, but we're still a ways away. Obviously there's still a slim chance, but I can see one out of the nine teams in Africa & Asia making it and Mexico is pretty much CONCACAF's only hope this tournament from what I've seen. BUT here's to hoping for an outright Cinderella to make the distance! Fingers crossed
[Not sure if you've ever seen this movie but I figured I'd make the reference
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