Which region has the best 8-16 teams?

I was watching Retals' stream the other day, and he mentioned that there's a huge drop-off in skill from the top 6 teams in EU to the rest of the region. I guess that makes sense since EU has some of the best teams in the world.

However, he also said that NA has a stronger 8th-to-16th tier of teams compared to EU. I completely disagree. I think sometimes the bubble teams in EU might look worse because of how strong the top EU teams are—they just get 4-0'd or 4-1'd by them.

I woould go as far as to say that the NA bubble scene is closer to SAM than EU

What do you guys think?