Although it would be nice to have an update taking some of the older devices up to Android 9, I am really more concerned that they continue to offer updates to fix bugs and increase functionality.
So far, they have been pretty good about doing this for the newer devices. My worry is that they will soon stop this abandoning their Android 6 devices the way they have abandoned their Android 4 devices such as the original Max of which I am an owner.
Now, what I would really love to see... an OTA update bringing eink colour to all their devices. I'm surprised they haven't already said that their R&D team is currently working on this and that such an update is impending.