In the first one there is a warning:
THIS SITE IS OUTDATED LEFT FOR ARCHIVAL PURPOSES. IT IS NOT AUTHORITATIVE SOURCE OF INFORMATION.
I have these questions:
Is its content not correct/suitable for learning?
Is it worth spending time reading and studying its content or is everything in it in the other, more current/official database and I'd rather dedicate it to this one?
Users database was as it's name says created by the users. Since main contributor has retired the content wasn't updated. This does not change educational value of materials present there.
The official KB is written by Amibroker's staff and it is just fine to use
I find the contents of these two knowledge bases very, very useful. I like to read each entry, trying to understand it and extracting parts of code to create my own knowledge base.
I don't know why entries stopped being added to the knowledge base since Oct 2017, what a shame.
I guess you can't maintain so many things at once