Alas, Nikonistas will say that us Canonistas all over the world live in a false reality... the number of cameras sold does not make one the better camera.
Ahhhh, so the majority of people are intentionally buying inferior cameras, or are not savvy enough to determine what's a better camera. If that thought is what lets you sleep at night.....
No, they're not savvy enough. Even shop assistants who advise people are not savvy enough.
By definition, masses of people can't be made of experts. It's quite clearly a paradox.
In fact, if we go by the number of units sold, then the 18-55 IS and the 50/1.8 are likely to be considered as the best lenses ever. Or in the same way, if Canon sells more rebels than 1DX, then Rebels are better.
Quite a childish way of reasoning.
What's interesting is that you list two lenses that obviously sell more units due to price, in my opinion that is. Now take DSLR's. Everybody complains about how Canon is overpriced relative to Nikon. Yet they still sell more of them. I'm going to guess it's because the majority of the market believes Canon to be a better DSLR. There has to be some reason why this is, don't you think?
Then we totally agree: sales figures mean nothing to us end users.
Pros and other people who are heavily invested in a system are obviously reluctant to change system. Canon has had the lead for more or less 20 years and they're still getting revenues on that, so it's hardly a measure of the situation in this exact moment.
On the other hand, consumers have most likely no deep understanding of specs, graphs, etc, and are heavily influenced by advertising, discounts, and whatever. So their choice is also hardly relevant in determining who is better than who.