Ah yes, I see in the release notes, "Rebuilt with WebExtension technology for improved ad blocking performance".
I'm not sure why they did that or whether it's actually improved, but the Apple-specific content blocker API is certainly not deprecated or anything like that.
The biggest difference is that the Safari content blocker API is native, in other words, Swift or Objective-C, whereas DeclarativeNetRequest (invented by Google) is a JavaScript API.
In-app views can't really have DNR unless they also have full browser extensions too.
I'm not sure why they did that or whether it's actually improved, but the Apple-specific content blocker API is certainly not deprecated or anything like that.
The biggest difference is that the Safari content blocker API is native, in other words, Swift or Objective-C, whereas DeclarativeNetRequest (invented by Google) is a JavaScript API.
In-app views can't really have DNR unless they also have full browser extensions too.