I think that's a totally fair point, and a reason that assumption might be incorrect. To be clear I don't mean "a pretty reasonable assumption" to mean it was

I think that's a totally fair point, and a reason that assumption might be incorrect. To be clear I don't mean "a pretty reasonable assumption" to mean it was exceptionally likely to be true (with, say 95% confidence) in my mind in this it's more like a 65% chance of being true. I guess I was using it as shorthand for "my prior is >50%" Anyway, I wouldn't be shocked if that assumption was wrong and if it is, it makes sense that it'd be for the reasons you outline