Aside from the farming & hard work as others had noted, as well as items that can’t even be obtained anymore, but on top of that I had some really important items that a player who is no longer with us gifted me 
And there are other personally meaningful items from experiences with friends that we had such good memories of.
Having a guild bank with all 7 pages basically full of items all disappear, I cant put it in words. Initially I was hopeful it’d be high priority one due to volume of people so might be back soon, but I’m getting more & more worried due to the lack of news / any form of update.
I just wanted to note that for various players this might be much more than a simple matter of gold or game time.
This isn’t just about 20 years of work, but also about losing incredibly sentimental items from all those years too.
EDIT: For clarity - this wasn’t directly in response to the above post, which I believe is more around making amends for the duration we’ve not had access to working guild banks, rather than fixing the actual bug / restoring all our items. I was just wanting to say getting our guild banks restored means a lot, possibly more than they realize due to the meaning behind certain items for players.