TLDR: Versions with limited usage will not appear in the Xcode Organizer Metrics.
We were curious why this is happening to our app aswell. We had 52 releases in 2021 and the Battery Usage section from Xcode Organiser Metrics menu shows us only 5 of them, while Scrolling section shows only 4 at the moment of writing this answer.
After doing some research and watching this WWDC20 session on Diagnose performance issues with the Xcode Organizer I have learned that apple is using some usage threshold for each version of the app to determine wether it should show up in the metrics or not. According to the linked session, in Xcode 12 they have lowered the required usage threshold by a factor of five.
Another thing is that now you will see a limited usage
icon attached to versions which have passed the new threshold but their usage is still low enough so you will need to be aware of the margin or error while analysing those metrics.
So even though the threshold have been lowered, it's still not really helpful If you update the app often like we do. Which is sad since we are not really able to provide improvements to these metrics since we do not really know with what we are dealing with. Let's hope future versions of Xcode will at more information about how much usage is enough, because apparently tens of thousands of users on a version are literally not enough for it to be included on a list.
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