Disclaimer: I use heavy emphasis in this post, but it's not my attention to attack; only to examine. I apologize in advance for any unintentional aggression.
Ignoring my own take on it for a moment, let's examine the language used on the picture.
How this reads to me, taking it word for word, is that this is your last chance to purchase the stream archives to get the FFX items, because they would no longer be available because you would no longer be able to purchase the stream archives. Nothing in the language used here says to me that the gear "will not be made available again, so get them now while you can" However,
the minions were said to be exclusive to each region's Fan Festival. Ergo, if they suddenly added those minions to the Mogstation, perhaps I'd be more understanding of the frustration.
That being said, it feels like people may be reading things that aren't explicitly said in that e-mail flyer. Looking into this further,
straight from the 2016-17 Fan Festival site:
Look at the wording of this line from that page. If we parse this sequentially, word for word, we get that the Lulu minion is
a Tokyo Fan Fest-exclusive, and you
also get a choice of the two attires.
The "exclusive modifier, as the line is written and as per my interpretation, does not apply to the attire, just the minion.
In regards to the Las Vegas stream archive; the same thing applies here. And finally, from
the Europe Fan Fest site,
it's written the exact same way here as well. Mentions of the
minion being exclusive but not the gear.
Now, I'll be the first to admit that I did not commit too much research into this, so there could've been a source I missed, and I am only human. I can interpret things incorrectly or miss details here and there, but
as far as I can tell, there's nothing to be argued here. Only the minions were, and remain, exclusive. Again, I could be wrong. This is only my interpretation and analysis of official materials. I can't present this as fact as I cannot be 100% sure of the intentions of Square Enix, the development team, or their partners for the Fan Festival.
TL;DR: In regards to the flyer posted earlier, the gear itself wasn't explicitly said to be exclusive to the Fan Fest streams; it was only said that it was the last chance to purchase the stream archives to get the items, which includes the gear. Only the minions were explicitly said to be exclusive, and the Fan Fest site blogs support this. If I missed anything, please feel free to bring it to my attention.