This is something I've considered wanting, and I'm glad it exists, but after some thought it's absolutely not at all what I want my Kobo to do. Much like how I wouldn't bring headphones or a Bluetooth speaker with me on a hike, or a laptop with me camping, I don't even want the option of games or anything other than a good reading experience when I'm using my e-reader. I'd assume this is a redundant take, but I don't even know if my Kobo can produce sounds, and I'd like to keep it that way.
What's tricky is that although I don't want it to be an unconstrained app platform, I do want the ability to integrate with services that host my things to read. Karakeep, RSS, Google Play Books or Internet Archive, etc.. but I think that could be handled in a more narrow fashion.