You're on the source. Ted has said right here in this forum that he's been focusing on other things. That's the most recent 'official' word we have, and it's from October 2017. Couple that with it also being said that right now they are focusing on bugs, not restoring functionality, and that ONE bug was fixed between RC14 and RC19 (and no, it isn't the mini channel issue).
BTW, I find it funny that you refer to the UI as Fisher-Price...that's something I've told TiVo as well. It's a great Fisher-Price My First TiVo, but I'm an adult and no longer require baby food.