Well they have said the UI has had a big revamp for Dragonflight. Maybe this is one of those things that are enroute to that.
I'm already under the understanding that I may not need some of my addons or they may need rewrites etc. So hopefully I'll get into testing to see how things look. Otherwise, people will have to wait until I've had time to test and fix/rewrite things
I recall NineSlice as something sneaking into dominance in the last expansion so maybe this one is pushing them forward again as you say to be the next system to use.