If you can achieve the desired UX on web, I see few reasons to build a native app. But of course it can be hard to work with web technology sometimes; Javascript and WASM can't do everything and they aren't the best developer experience compared to more moderns languages.

Even for offline usage, there is increasing support for progressive web apps. For example, I don't even need to be connected to the internet to use Exaclidraw after I've loaded the app once and installed it as a PWA.

Then there are times when you simply need access to native platform APIs. SQLite is a a very important technology that isn't easily used from a web app. Most of the powerful APIs you get from an OS like the file system or graphics APIs are extremely watered down for the web.