Actually, she was correct on a number of levels.
First of all, her title gives credit to each individual personality type as being unique from each other, some less unique than others and some more unique than others. You can certainly subject uniqueness to gradation. It's an arbitrary system of gradation, but everything is arbitrary.
Second of all, literal definition (denotation) doesn't drive language. Denotation is the word when studied in how it's been used, and historically how it's been interpreted to mean. Connotation is the driving mechanism of language, since it's the way the word is used in practical conversation, which is what denotation is studying. And since language moves so fast, even the best efforts (which there certainly have been in the past) can't keep up with the evolution of language. So of course dictionaries aren't up to date, since the way a word is being used popularly only just then gets added to the long list of words waiting to be updated.
Unique as a word has been drawn into meaning something that has peculiar or non-typical qualities, unlike it's past definition of being one-of-a-kind. Its structural grammar was correct, and I'm not sure how you could be unsure of what the meaning is. She clearly set up "unique" as a juxtaposition to "normal", so if you can understand "more normal", why can't you understand that "less unique" is opposite of "more normal"? That's how English works. And English doesn't favor people whose brains are rigid on meanings, so... you're gonna have a bad time.
To the OP:
I think it has more to do with the fact that the SJ population is larger than the SJ population being more normal. Normality in a society is driven by the characteristics of the members of the population, and since SJs comprise more of the population, they're therefor more normal. If NFs were the larger percent of the population, they'd be more normal, since the norm would be skewed towards them.
And like other people have said, they're the drivers of our societies. It's an SJ that's more likely to go into administration or management at some point, and they're the doers who get systems in motion. I think we give "normal" too much weight as "boring". I'm not saying SJs aren't boring (I've met some that are boring as all fuck). But if we didn't have SJs in our society, we'd be screwed. I wouldn't take my mom as any type other than ESFJ, even if we have some core misunderstandings. And it was my ESTJ grandmother that raised my mom, and owned three businesses and was a bank teller and real estate agent. If I need something sewn or something cooked, it's my grandmother I'll go to. Sure, she might think 7/10 paintings in our city's art museum are ugly and meaningless, or that scientists have gone off the deep end with their research on the travel habits of sea cucumbers, but if a store doesn't give us credit for a sale that's going on, she's a pit bull like neither me more my mom can be. She once shook her cane at a judge over a parking ticket.
It takes all types. Normality is a moot point. It's the minority (the unique ones) that has to do constant upkeep on uniqueness as a positive attribute. In Japan and Norway it's something horrible to be.
You can still be a special snowflake.
