I hope that StackOverflow people understand this. And that they do not panic because their usage/engagement metrics is down quite a bit over the last years.
I've written a lot of PDFs about Amazon Redshift - serious stuff, deep technical investigations and explanations, published along with the source code which produces the evidence which the PDF is based on - and when people asked questions where I'd written up the answer, I pointed them at the appropriate PDF.
After some months, I received a direct message, which looked to me to be a pro-forma, a standard message sent in this situation, from the staff that I was promoting my site and I should not do so. It was well written and polite.
That's fine - I have no problems with that, it's their web-site.
What I did not like, however, and what came over as slimey, was that the staff had also deleted every post I had made.
This was not mentioned, at all, in the well written and polite message, which then of course became disingenuous. If you're going to do something serious like that, you need to tell people, not let them discover it for themselves.
This was for all posts, where I'd explained something directly or pointed to a PDF - presumably it's a standard action SO take in this situation.
