Typically, I wouldn't use the T word when describing people, but more when describing a place. Similarly, we might describe a restaurant as being the "Veggie" place rather than an animal protein challenged restaurant. In some ways we shouldn't use slang terminology, however as you say, it really is only a problem when used in a derogatory manner.
It is indeed true that we should not be creating more barriers between 'us and them' in any situation. When we consider things in those terms it is because we are trying to create or feel an air of superiority. Thus, it is ultimately us, ourselves that create division which does not necessarily need to exist. For sure the ultimate solution would be that we should have the right to choose everywhere, and there should not need to be places that were specifically naturist or "textile". As you were saying in your latest blog article, the one thing that would make Paloma park perfect after visiting the beach, would be not needing to dress to visit.
For sure we should try to not use words in a derogatory way, but it is sad how many words are becoming accused of being derogatory, so we have to find new clever ways of saying the same thing in a more PC compliant manner. However, 10 or 20 years later those terms are then considered derogatory. And to call anything "challenged" is derogatory. After all we would never consider calling somebody ethnically challenged, as that is 100% racially insensitive. So, to call a short person "height challenged" or someone wearing a bathing suit “nudity challenged” or an MP who made a series of mistakes “hard of thinking” is definitely derogatory, even if seemingly clever terminology.
As you point out, to say something is non-whatever is somewhat derogatory as it implies one is superior to the other. Again we would not term people as being coloured or non-coloured anymore. That is a ridiculous term anyway as Caucasian people (and that is the wrong term in itself, as we don't really look like people from the Caucasus) still have a colour, we aren't transparent!
Actually, in a lot of ways i get the feeling that the new PC way of saying things is even more divisive and derogatory than the original terminology. Most of the time terminology was not intended to be used in a derogatory manner, it is only the connotations that society has put on those terms over time. Surely, we are all people, all equal and have equal standing everywhere, clothed, unclothed, black, white, purple, or green.
Ultimately even a 'Textile' is still a 'naturist' or 'nudist' under their clothes :)
The issue is that we as a species we do love a division to differentiate us against them. We see it everywhere from local schools to sports teams to communities, and so on. Competition is natural in this universe, despite how much we try to shrug it off, so we do tend to enjoy language that divides. The fact is, that nudist beaches do tend to be 500m stuck behind the rocks over the cliff way on yonder, such as one of the first official nude beaches in the UK at the east end of Hastings. I know this well as I spent my first 10 years in Hastings, with the reasoning of "Oh well they can't do much harm there, as the blue rinse brigade will never see them".
If we want to go with a fun way of differentiating how users can appreciate the beach, perhaps we could use terminology such as "Sausage Beach" and "Bikini Bottom". Of course I am facetious, but I would still argue that perhaps we could try to position it that every beach can be nude friendly without having to resort to terminology such as textile and nudist. When we are on a clothed beach, we are wearing some clothes, and on a naturist beach we are nude, so what is wrong with sticking with those sorts of terms, whilst we are in the current situation in most of the world.
Interestingly I was watching an old BBC documentary on naturism on youtube a few days ago, and it seems this whole debate and many others we have been discussing, are more that 50 years old. The whole point of having to be "clothed" on a beach is relatively modern in human history. Maybe it is sometimes that the hidden nude beaches are that way because it is where those of us who shunned societies demands for "modesty" had always gathered, and they never became a "clothed" beach.
Despite any of this, I would still argue why do we need to differentiate nude beaches from clothed beaches, so why do we need a term such as "Textile" in a naturist setting. We only ever really use it when trying to defend our "faction" amongst ourselves. Consider a naturist saying, "Oh well I think that Textiles are a bit silly to insist on wearing clothes when it is so hot!", whilst seemingly factual it is still derogatory.
After all we don't call ourselves "textiles" because we simply put on clothes, indeed most of us would say we are dressed when required for comfort or to conform to society. Thus it is us as a "minority", which is bringing in the divisiveness, while arguing there should be none. After all, most of us here would argue that there is no need for name calling or bullying, we wish to simply have a society where being nude is normal and not fetishised. Thus we should not be name calling ourselves, remember our mothers old saying "Those in glass houses should not throw stones".