Seems nice! I use FCM (Firebase) which does this for Android and iOS, which does require some setup, but it's not too bad

unfortunately, Declarative Web Push only supports WebKit, means Android cannot use it.

Mozilla have indicated they are positive on the feature:

https://mozilla.github.io/standards-positions/#declarative-w...

Chromium has a bug filed:

https://issues.chromium.org/issues/382298314

So hopefully this will move forward with other browsers.