I think that’s a false analogy. A face mask surely contains part of a sneeze. Aerosols play an important part in the spread of many airborn viruses, and masks certainly change characteristics of mouth born aerosols.

To see a slightly tongue in cheek example, here’s masks vs flamible liquids. https://m.youtube.com/watch?v=x6cTDGqcUpA

That said, you are probably correct in that aerosols still escape most masks, and will saturate an enclosed area in a much faster time period than we have an intuition for. Still, I have reason to believe from numbers I’ve seen that masks reduce the odds of getting covid by 3-18% in any given hour of exposure. And reduction in spreading to others may be similarly effective. But, since you’re rolling the dice with each hour such a small amount of safety becomes increasingly less useful.

I’m willing to give the benefit of doubt and say that “masks are ineffective” as being shorthand for “if you spend 8 hours in an enclosed space with someone masks alone aren’t going to give enough benefit to be worth it.