Well, my personal everyday phone is affected, and it drains pretty fast (when I'm on mobile data).
And there are comments in the bug report about very noticeable, very short, total "lifetime" after charging.
On the other hand, yes, it could be a bug in how it's reported, and may explain why Aqua's affected so much (with multiple network connections, one per account at least... if each connection is counted).
I already made a test app for this, perhaps it would be worth making it open multiple connections at a time, to see if the reported %% becomes higher.
And yet, if this is just a simple reporting bug, not sure why 1) it's not fixed yet and 2) there are no comments at all from Google people.
One way to explain it is that the bug is somewhere between Android code and low-level cell modem code which they get from Qualcomm and other chipset manufacturers. But that's just my conjecture of course.