Am I wrong to assume that this doesn't add anything beyond what uBlock on medium mode does already? Except (perhaps) ease-of-use and the blocking of first-party trackers; if those even exist*.
Don't get me wrong; I love EFF's work and their commitment to digital privacy. I just want to understand if I, personally, would need it.
Currently Privacy Badger will de-mangle Google-mangled links in their search results. You can see it discussed in this episode of Security Now! https://www.youtube.com/watch?v=suT0E53jX40 Here are the show notes (ctrl+f for "badger" and you'll have all the information you need): https://www.grc.com/sn/SN-945-Notes.pdf
I wasn't using it until I saw this so I installed it despite using uBlock Origin.
It's probably overkill, I think. Based on my understanding of it, there's a chance Privacy Badger will help you out in a scenario if you happen to re-enable too many things while unbreaking websites in Medium Mode:
Privacy Badger was born out of our desire for an extension that would automatically analyze and block any tracker that violated consent, and that would use algorithmic methods to decide what is and isn’t tracking. But when and where that learning happens has evolved over the years.
But at that point, it would theoretically only catch something uBlock Origin blocklists somehow missed... IMO, highly unlikely.
If you are good at navigating the web on uBlock Medium Mode, and are okay doing the initial "troubleshooting," to unbreak first time visits to websites, then you probably do not need it. I mean, most tracker won't run without Java. Also, on Medium mode, you get to see most ad companies' domains which you can then just block Globally. You can also use uBlock's selector tool to remove specific parts of webpage. I find that I use it a lot to remove cookie prompts and others, like YT prompts. So I van use it without having to sign on.
Albeit there is some overlap, I use still uBlock on Medium Mode along uMatrix since I need a bit more granular control on the sites I use. On top of LibreRedirect to avoid some of the biggest data miners.
You should be fine.
Just use uBlock Origin, does the same thing but one less extension to fingerprint.