It was done based on this post here:
If removing this permission by default from compiled apps resolves the issue of most App Inventor apps being marked as trojans, then it is worth people having to update their extensions if they need to. Every major release of App Inventor would then end up with a bunch of posts that App Inventor has been "hacked," which is not the case.
Importantly:
- As of Sept 2019, only 2% of App Inventor projects made use of extensions. It follows that fewer than those use extensions to check network connectivity.
- The companion still includes the permission because it needs to check the network state when establishing peering with the web session, so any extensions will continue to work while live testing until the author updates the extension.