I agree with you 100%, though arguably what you could be describing is how docker changed your deployment workflow, not your development workflow (although with devcontainers that line is blurry, as you say).

I guess it's worth keeping in mind that Justin only quit Docker a few months ago, and his long tenure as CTO there will have (obviously) informed the majority of the opinions in the article. I think the deployment over development spin and some of the other takes there more closely reflect the conversations he had with large corp paying customers at the exec level than the workflows of solo devs that switch dev environments much more frequently than most etc.