It is fascinating and I love to see it. Ultimately though, why not build your own? I think that in part is what we're beginning to see-- highly customized and personalized software. I take most of these as inspiration these days and just build my own. Nothing you can't hammer out with a few good Claude sessions.
But why build your own from scratch when you can do it on top one extensible UI platform that already has all of your organizational context, not to mention coding agents already built-in that you can just tell it to build & deploy your personalized workflow softwaree from scratch? ;-)
These new experiences are built atop layers and layers of bedrock libraries that we, generally, don't reinvent. Or we reinvent one or two.
What's notable to me is that ux doesn't so far generally have this behavior. That as per this post people just build a new app, a new experience.
I want to believe over time we'll have better composable & malleable ux experiences atop broader platforms for us. That over time the "go it alone" path has other worth ways to innovate that use a more substantial shared base. It's dangerous to go it alone, and doing so equipped with just our wooden sword and some courage and perhaps an LLM wisp is an amazing adventure, but I think the survival rate & impact would be much better if we had more general ux systems that supported better innovation atop them, and if less people did the pure "why not build your own" path.