Sketch lost the market to Figma, and now Figma is losing the market to vibe coding.
I'm not sure what the value proposition of Sketch is these days apart from local, non-cloud editing (although you can even get that with a pretty decent UI these days with Lunacy).
Doesn't Apple already have a loose competitor to Figma? https://en.wikipedia.org/wiki/Freeform_%28Apple%29
Sketch has always been the app I use for quick throwing-together of things. Figma seems designed for specifically corporate design documents which is icky.
Vector screen-destined assets. Illustrator is print-centric and awkward for the use case, and while Photoshop is technically capable of it that's not what it's made for (also, Adobe CC is just way too bloated for its own good). Figma is oriented around mockups and not as good for assets.
There are also platforms which are less vibe-friendly, and old style mockups can still be useful when nailing down a design system across platforms.