"The containment procedures are questionable — that's not how the Foundation normally handles sapient anomalies, even dangerous ones."
Where is this written? What rule says that sapient anomalies need to be handled in a specific way? Additionally, this is a poor argument that this article should be a -j because as I see the containment procedures, they are a reasonable way of containing an anomaly so it doesn't do harm to the larger population. A -j wouldn't even consider such measures.
"There would be an investigation into when the anomaly became anomalous, and the circumstances of the change, to determine whether other instances could manifest. Etc etc."
This is asking way too much of the author. The point of an SCP article is to tell a cohesive narrative through clinical tone, not to over-elaborate on every single detail. The details you are suggesting here add nothing to the overarching narrative of the article, and would actually deter from the article's straightforward narrative.
"If you make it a -J you can go Full Silly with it, but on the mainlist the Foundation should take the Booming Boomer seriously and do the dry work of establishing how unique the phenomenon is. The interview isn't nearly enough."
Still asking too much of what is supposed to be a short and punchy article. Additionally, going "full silly" is perfectly acceptable in a mainlist article as long as the Foundation itself isn't "full silly." Here, the anomaly is silly, but the way the Foundation handles the anomaly certainly isn't.
Overall, I think your arguments for why this should be a -j are invalid.
