Agree with the sentiment, but 2018 was a bad year to use as an example. Olympic year Worlds are always scarcely attended, whereas this season Russia will most likely send 3A (2018 Russia sent Stanislava, who ended up 19th), Japan will send 1 more, and 2 Korean ladies will be more than competitive.
Assuming Emily and Alison are both sent to Worlds, I think it will be very tough for them to have their placements add up to 28 or less. Not impossible, but the level of competition has gone up dramatically and they will have to be close to perfect.
No offense to the Canadian ladies, but the top 10 (3 Russia + 3 Japan + 2 US + 2 Korea) can have meltdowns but still be expected to score higher. Emily and Alison don't have any reputation to prop themselves up, and reputation scoring is huge at Worlds. Even at home for Skate Canada in a limited field, the Canadian ladies finished dead last in 10th, 11th, 12th (albeit it wasn't Emily and Alison). 13th & 14th or 13th & 15th might be semi-realistic, but neither can afford any mistakes.
Canada has relied on Kaetlyn and Gabby for far too long, and no one else has really stepped up. Maybe losing another spot at Worlds will be a wake up call to catch up with the other countries. I do think Gabby being sent to Worlds will be Canada's highest likelihood of retaining 2 spots (she has the reputation and has time to fix at least some of her current issues), but I don't think it would be the right choice. Gabby needs time to fix her underlying issues, and Canada as a nation will not develop the next generation by sending Gabby over and over, especially when she finished eighth at a weak home field.