All of my content also disappeared in mid January this year but I didn’t get banned from the forum. My PM to Rob was unanswered.
There was a forum built by a Swiss guy who then, unfortunately, died. Ownership of that forum was tied up in legalities. A member of the forum where this was discussed, who was an IT whizz, was able to take a cloned copy of that original website. I’m sure there must be equally talented members on this forum that could do likewise for this forum?
This happens with various sites for me also from time to time. The solution is usually to quit the browser, open the browser and clear all cookies and data storage (2 separate things!), and restart the browser once more. PITA because you have to re-log into everything again.
I've got quite a few of those collected on various visits. In case you're not aware of the history, which will, hopefully, be confirmed by one of our US members, they aren't really rare but are very uncommon, despite being legal tender. They were often used to pay US military service personnel and so would be in more common circulation in areas where military bases were sited. I think I got my first one in change from a gas station in Nevada - the rest I got from a bank, just for the novelty.
It is possible to scrape posts from forums but it's not a simple task to get it working. It has to be customised for the site's configuration or skin. I'm not aware of another method that doesn't involve getting to the back-end database. That Swiss site is an example of how ownership and management need to be considered and set up for continuity in the face of unexpected events, If you're building a community, there should be reassurance for the people that create all the content and build relationships that it won't just disappear one day.