Isn't that how it used to be? The Knierims were 10th at 2017 worlds and the US only got one spot for the Olympics. I'm not sure when it changed.
No. It used to be that a country got
all of its spots based on the top-level skaters in order, even if the lowest-ranked team didn't even make the free skate. The allocation ran out with the team above the Knierims, leaving one spot for the US. Back then, if you earned one or more spots at Worlds, you couldn't compete at the Olympic qualifier to get another, so the US couldn't compete for a second, even though they'd earned it numerically for Worlds.
Now, if the top team(s) earn(s) two or three spots, the country gets all of them outright if all make the free, even if the second (of two) or third (of three) skater placed lower than a team that is cut out of the spots because of the multiples rule.
I believe Tony is suggesting that the spots are allocated one at a time in the order of the actual finish until the Worlds limit is reached. If a country earns two or three spots for Worlds, but only one or two in order, they can attend the OQE for the last spot.
ETA: Example from Boston:
Harris/Chan were 19th. Fabbri/Ayer were 20th. Canada earned three spots outright, because Gilles/Poirier and Lajoie/Lagha totaled 9 (<13), and Fabbri/Ayer made the FD. Australia got bupkis, and that's why Harris/Chan have to try to earn a spot in Beijing.
Under Tony's proposal, Harris/Chan would have gotten the last Worlds allocation spot, and a Canadian team would be in Beijing to earn the third spot.