A downward trend in the number of questions doesn't imply the site was in decline, since there's only so many questions you can ask about a given technology, so would-be question askers find the answer via search engine rather than having to create a new question on the site.

Tangental, but I tried plotting number of questions by month including deleted questions. It shows similar trends to questions by month (so nothing particularly interesting): https://imgur.com/a/NLLB3OK

Query: https://data.stackexchange.com/stackoverflow/query/edit/1969...