If you want to engage productively, remember that people tend to say things they think are true, so look for a way to read it that makes sense rather than going out of your way to find a way to read it that makes it false. (I guess nitpicking the phrasing for a "middlebrow dismissal" is the best way to get upvotes here nowadays).
> nothing about this list implies "runs fast."
It doesn't imply it, but it enables it; read "allow" that way.
> Is a memory leak meant to be the "worst sort of bug" or a "security vulnerability?"
Maybe the one that makes sense rather than the one that doesn't make sense.
> The implication is that memory-safe languages do not have memory leaks, which is completely false.
There's no such implication, only that memory-unsafety leads to memory leaks, which is true.
> Or is Swift meant to be included in "garbage collected languages?"
Yes it is.
> No these are not the same and this is an absurdly wrong conflation.
They are the same; traditional dynamic typing is exactly unityping. That it's possible to combine dynamic typing with other things just means that alternatives are possible, not that dynamic typing is something different.