Firstly I must say, I have no idea what you said there or what the "offending" conversation was about.
But...
I don't think you are overreacting.
First, if they didn't phrase their notification of your ban properly, that was not bright of them.
I see that constantly on websites and I realize I'm the worst offender of grammar, but when it's an important statement, I try to get the exact idea across.
Making a statement that sounds like a permanent account ban is a pretty careless thing to do and can really piss someone off.
Second, I get banning someone from forums, but from their paid content is kinda stupid... It's not like it's a physical store where you are gonna get pissed off and start knocking over displays or throwing their potato chips around.
Denying one access to their purchases is more likely to escalate a situation then teach anyone a lesson, because if you were doing an illustration job or something where you needed access to your paid content right away they just unnecessarily screwed you monetarily for no good reason.
What would that solve?
I've had so many posts removed from DAZ where someone thought I meant something I absolutely did not, it got stupid to even bother making posts, yes I'm infamous for my satirical innuendo, but if get a notification that a post was removed and I have no idea what I said (and I stopped making long posts there a while ago)... (I only do that here more or less... Hivewire is cool)... And I have to play back in my mind what I wrote and then run over it a dozen time to even get a semblance of something that could be remotely interpreted as forbidden... I get annoyed too.
It's annoying to feel chastised for something that's completely inoffensive in normal conversation.
I'm not saying you were wrong or right, since I don't know what went down... but it is human nature to feel bothered and upset and completely understandable that you should feel this way.
Don't let it get to you.
I don't know how their system works, but it seems very evident that some sites have mods that are quicker to push a button then others...
Maybe it's a language issue, or they are sensitive or misinterpret the meaning or are overworked...
I'm pretty one site I know of has a sociopathic capybara as a mod, but that's probably just because they needed someone for the off hours and capybaras never keep normal hours and work cheaply.
And sorry about the North Korea comparison, I just couldn't come up with a better embargoed rouge nation, quickly...
Wasn't there some guy who took over an old WW2 gun installation in the North Sea off the coast of England a while back and declared himself a nation?...
That sounds fantastically benignly insane and fun and I'm sure he has at least one embargo on him...
So I probably should have looked that up and used that.
What I actually meant was the next time someone gets all up in your face in the real world, you can use the line "Oh, you think you are bad bro? I've had embargoes place on me, yo..."
Then again I don't know how many bar room brawls you get into and how literate your opponents are.
Either way, don't feel bad and I don't think your reactions or subsequent feelings are unusual or unjustified.