Chromium is awesome and all, but it's just way overkill for many apps, and doesn't make sense for the download size and the need to support auto-update for security features.
I personally prefer the system webview because you don’t have to rush update your app for every chromium security update. And on the web making things cross browser is a normal part of the job and instinct imo.
But there are a ton of early startups that only have bandwidth to support chrome/chromium in their complex webapps and want a quick way to port their web app to desktop app. For them taking on the security burden and increasing bundle size is a good tradeoff to getting that consistency.
Luckily electrobun has a custom zig bsdiff implementation that generates update diffs as small as 4KB and self extracting executable that uses zstd so at least the file size is less relevant of a concern compared to electron.
I'm interested to hear more about this—if you're using security-sensitive features in a WebView, aren't you then at the mercy of the OS to patch them whenever they see fit? And if you're not using features that have security implications, why do you need the latest version of Chromium at all times?