Tauri does not do this in all cases, as WebkitGTK on Linux has performance issues and is often the ugly duckling of everything.
I also feel like I will have to, yet again, trot out the comment from a Slack dev that explains why they moved _from_ per-platform webviews to Chromium. This isn't new ground being charted, plenty of companies and teams have been down this path and Electron exists for a reason.
(I am not saying Electron is _good_, I am saying that Tauri isn't the holy grail people make it out to be)
According to https://slack.engineering/building-hybrid-applications-with-..., Slack never used multiple different per-platform webviews. The earliest version of their desktop app was Mac-only and used the OS-native WebView API, but they switched to Electron at the same time they started work on making the app cross-platform. At the time, not only did Tauri not exist, but neither did the WebView2 API that it uses under the hood on Windows; they would have had to use the WebBrowser ActiveX control, which uses Internet Explorer's Trident engine and was already deprecated. So it's not so much that they rejected per-platform webviews, as that per-platform webviews were not yet really available as an option on desktop.
Isn't Spotify using CEF (Chromium Embedded Framework) rather than Electron?
Regardless, your point stands: it's a bundled Chromium on all platforms
https://news.ycombinator.com/item?id=18763449
It took me 2 seconds to find in Google, and you're splitting hairs if you think it being macOS-only was the point of my comment. Their second bullet point is just as true today as it was back then.
Slack in web works fine in several platform browsers still though.
That's not what the comment was even remotely disputing.