(Not picking your post in particular)There are tweets from people who worked at both WotC and Paizo in the article. They're saying that they had access to internal sales figures, and that Pathfinder didn't outsell 4e D&D. I don't understand why they'd have a motivation to mislead folks.
There is a pile of problems with this seemingly never-ending discussion ( and the similar one about White Wolf in the 90s ), which boils down to scope and context.
Folks inside the companies report know their direct sales volume, the volume they push into distribution, and with some distribution partners - a degree of sell-through. Folks from the self-reporting survey are 1) self-reporting 2) As best I can remember, only FLGS. These are at different ends of the sales cycle and can both be accurate and contradictory at the same time. This is without asking whether this is by title or rolled up across lines.
Ultimately, there is no way to resolve this as there is no public data of statistically trustworthy value. It's even worse for the 90s...