[copascetic]

If you'd carefully reread the post you'll see that your first assertion is false. It contains this sentence: "But it is a meaningfully distinct kind of type safety from the one I highlighted a year ago, one that is far weaker." The antecedent of "one" is "type safety", which is being provided, just, weaker, not "not type safety" as you claim.

As for whether the example is being "dismissed" or not, I also think that's manifestly false. See: "[this tradeoff] is often a very good one!" while still diving into exactly what the tradeoff is.