> This is more like people arguing over "proper" English, the point of language is to communicate ideas.
ur s0 rait, eye d0nt nnno wy ne1 b0dderz tu b3 "proppr"!!!!1!!
</sarcasm>
You are correct that communication is the point. Words do communicate a message. So too does disrespect for propriety: it communicates the message that the person who is ignorant or disrespectful of proper language is either uneducated or immature, and that in turn implies that such a person’s statements and opinions should be discounted if not ignored entirely.
Words and terms mean things. The term ‘REST’ was coined to mean something. I contend that the thing ‘REST’ originally denoted is a valuable thing to discuss, and a valuable thing to employ (I could be wrong, but how easy will it be for us to debate that if we can’t even agree on a term for the thing?).
It’s similar to the ironic use of the word ‘literally.’ The word has a useful meaning, there is already the word ‘figuratively’ which can be used to mean ‘not literally’ and a good replacement for the proper meaning of ‘literally’ doesn’t spring to mind: misusing it just decreases clarity and hinders communication.
> If my API is supposed to rely on content-type, how many different representations do I need? JSON is a given anymore, and maybe XML, but why not plain text, why not PDF?
Whether something is JSON or XML is independent of the representation — they are serialisations (or encodings) of a representation. E.g. {"type": "foo","id":1}, <foo id="1"/>, <foo><id>1</id></foo> and (foo (id 1)) all encode the same representation.
>misusing it just decreases clarity and hinders communication
There is no such thing as "misusing language". Language changes. It always does.
Maybe you grew up in an area of the world where it's really consistent everywhere, but in my experience I'm going to have a harder time understanding people even two to three villages away.
Because language always changes.
Words mean a particular thing at a point in time and space. At another one, they might mean something completely different. And that's fine.
You can like it or dislike it, that's up to you. However, I'd say every little bit of negative thoughts in that area only serve to make yourself miserable, since humanity and language at large just aren't consistent.
And that's ok. Be it REST, literally or even a normal word such as 'nice', which used to mean something like 'foolish'.
Again, language is inconsistent by default and meanings never stay the same for long - the more a terminus technicus gets adapted by the wider population, the more its meaning gets widened and/or changed.
One solution for this is to just say "REST in its original meaning" when referring to what is now the exception instead of the norm.