It's tough to get developers to care about things like offline-first, because it's tough for them to convince managers to allow them to spend time on a feature that won't work on iOS (since it won't work in Safari, and Apple has banned other browser engines on their platform).
Ultimately it's users that lose out but also the web as a platform, as it pushes people, like the author of the article, towards walled-garden solutions like native apps.
Apple is looking for service worker use-cases, so if it's something you're interested in, let them know https://lists.webkit.org/pipermail/webkit-dev/2017-July/0292....
Can you elaborate on this a bit? I primarily use Chrome as my browser on iOS. Is it really just running the Safari engine under the hood?