The first is that the group I identified with was hostile to another group. Having been through that in various flavors, outside of the type-ism, I am very intolerant of that behaviour, and when it comes out directly, I get quite irritated. This is reactionary, and as such, not everyone will understand it.
The second part of that is that I also have perspective on what it means to be both. For all intents and purposes, MBTI Ns are imbalanced. The nature of population distribution says that all Ns are at the tail end, essentially starting one standard deviation above normal. It isn't so much that this is a disadvantage, but identification within that kind of distribution is harmful. Any N should be seeking balance. So, when I actively see Ns rejecting balance to remain inside N (compound that with doing it because they want to be 'special' rather than it being their nature), it is universally unhealthy and brings back memories of what I was trying to force myself to be.
That's the catch with personalities - it's just that in MBTI, the effective range of ~30-70% that are Ss are the only ones that are naturally balanced on the divide, which would include 35-40% of the population, almost all defined as Ss.
How do you describe 75% of the population meaningfully, in a few phrases? Of course you can isolate the 'top' group of 25% and describe them in glowing terms, but what about the 50-75%? You know, the ones with strong N tendencies as well, but more balanced? What about the 25-50%, the ones with weaker S tendencies, but still generally balanced? Only the 1-25% group would be "opposite" to the N population, really.
If we applied the same distribution to the other divides, what do you think would happen? We do have one example - introverts and extroverts have been under the illusion they are outnumbered. I still hear "poor introverts" from time to time.
Identification is very dangerous. MBTI can help you understand yourself, but it can also lead to a great deal of bias. All of the 'poor N' stuff falls apart at the slightest touch. The N definition literally gives almost all the advantages to that side of the equation, and not surprisingly, has weak validity. The reason why most of the population can identify with being N is because the N descriptions can be extremely broad - everything from creative, to intelligent, to leadership, etc. It captures all of those that would normally be in the 50-100%, if not more, as a result. The second is that it essentially engineers tail end support for what would normally be considered 'strongly expressed' and 'worse', both meaning that balanced individuals that should be 'X' within MBTI are denoted as Ss and that those that do end up in the N world are well outside norm, leading to the whole 'I'm different and special'. Again, both are engineered by distribution and is not generally supported (ignoring function theory).
Those that test N should be 'happy' that they tested that, then work very hard to become balanced - not embrace it. Their only real disadvantage is in being imbalanced. And looking down on those that are balanced are laughable at best, since they tend to have most of the N advantages anyway.