Another misconception. If rank doesn't play a part, then the seeding is meaningless. Then there should not be any qualification rounds. Then those with very low WR should be permitted to enter tournaments and there should be no quota? I'm sure you know that the higher WR players do have advantages in any draw.
If you don't have an appropriate WR, then you may not be accepted into certain tournaments, like the SS Finals, the Olympics, the WC?
If you say that WR plays a part but
upsets can happen, then I'll agree with you.