That sounds plausible and might be true.

Also I have to say that I am a rather tall guy and the only height-adjustable desk that had a usable maximum height for me e.g. was the one from Ikea.
I think it is definitely not a specific Ikea or Swedish thing or has anything to do with the people being smaller (If anything, I think to remember that typical US citizens are actually smaller on average than most of the people in the northern parts of Europe...)