The point was that, in fairness to Payn, his comment was not utter US cluelessness, cultural chauvinism, or assuming that everyone knew how things work in Eagle-land. They had every reason to believe their comment was close to universal in broad strokes, that people would catch the relevant universal theme (large metal box=hard to move) and had even included a helpful reference point.
I have no idea how you decided this was x-splaining to you. I would think the inclusion of the metric conversion* would be an indicator that it was never about you**, but about their post, which was literally the only thing I covered in my response.
*clearly not for Canadians, which I assure you I did not know about you, as this was never about you.
**'for anyone,' as I included in my post.
Edit: big long rest of post cross-posted with mod-text.