We have far too many stickies. I can't account for the merit of many that did end up stickied, but before I add to that chaos, I am going to have to be solidly convinced it is a thread of long term importance. There are moderators who feel differently than I do, and if you get them on a good day, you might get a sticky from them, but, overall, I don't think stickies are a great thing to have, and the moderator team would rather cull them down than add to them.
The simple answer for the thread you linked to is this: it's on a board that is not already overrun with stickies, so it would appear there was "room" for it. When it comes to stickies, it very much makes a difference which board you are talking about.
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).