Well the notifications on your web site doesn't provide the full idea of how limited it is in Safari. We have to ask users to install the shortcut before allowing notifications with Safari. Guess how many users actually go through with installing the shortcut? Nearly none.

If we had to ask users to go into their settings and switch the "enable notifications" flag we wouldn't call that supporting anything. The whole process of installing a shortcut to even get to the point where we can ask for notifications is even more convoluted on iOS.