> Sure, but taking your video editor example, what advantages does an in-browser app provide over a native application like DaVinci Resolve

It's the issue of friction. Also, good webapps are often _better_ than native apps, as they can support tabs.

> And if this is such a compelling value proposition for full-featured desktop productivity applications, why didn't Java Web Start set the world on fire?

Because it relied on Java and SWING, which were a disaster for desktop apps.

> Also, good webapps are often _better_ than native apps, as they can support tabs

All the native apps I use support tabs, its a basic feature of the macOS windowing APIs https://developer.apple.com/documentation/appkit/nswindowtab...