Embedding a web view has a ton of tradeoffs. A good implementation of SDUI will support all the native platform features like accessibility, dark mode, localization. Not to mention the user experience is much more natural when the SDUI implementation is rendered using the same frameworks as the rest of the app.
For performance reasons
doubt it's much faster for just rendering a list - and you get a lot less than webview offers - html, css, svg, javascript etc etc.
web app won't integrate like native components can. here, it uses idioms of iOS and Android UI including navigation etc. It's just doesn't have this feeling of foreign component. In addition you get no-cost UI update for never/older system versions (since it uses platform components). Not trying to mimick platform.
No-cost UI updates are UB, not some gift that you should take for granted. If your program is liable to change without your consent or control in the foreseeable future, I'd consider that a bug.
I've meant platform UI changes, like when iOS changes how button looks from version to version etc.