Your search may be like: "What is the most common dimension for obscure item X?"
And you are the one person who stated the dimensions for your version of such an item, but didn't in any way imply its typical or that there even is a typical dimension. And like you said, it's just you, not 20 people saying the same thing.
And google will happily say: "Typically item X comes in [the dimensions you state] because [some reason it totally made up]."