I personally would love to use more upstream repositories (would save us the headaches of maintaining forks). In most cases, the reason we made a fork is because there was some tweak that was useful/necessary for ODM, but probably would not have been accepted upstream due to the specificity of the tweak. In some projects (like OpenSfM) we deviated significantly because we added new features and fixes (and Meta has showed little interest in accepting outside contributions).
There’s also the issue that in more than a few instances, upstream decided to yank releases or git tags, which caused our build to stop working, so I’ve found it sometimes easier to keep a fork and update our fork when we’re ready to update, but that’s been project dependent and thankfully most projects do not randomly yank releases.
If there are some projects (e.g. entwine, untwine) which can be migrated to using upstream, the first step would be to look at the changes (if any) that might have been added to our forks and port those upstream and we’d love help with that.