My original view on Deno and JSR was positive and optimistic (it's all there on my blog). I've been using it for years and I still use Deno because it has more convenient/ergonomic APIs than Node.
If Deno halving the Deploy regions twice from 35 to 12, and 12 to 6 doesn't convince you then I don't know what will
It doesn’t convince me. You seem to be determined to conflate two very different things. If I use Deno it’s because it’s a language runtime. Deno Deploy is as the name says.
The title should be, if anything, “the decline of an after thought deployment tool”.