Hello.
After using 17.6.1 build 21G101 before, and build 21G93 after, on the same A15 device, under the same conditions (same times, same apps -Wipr v.1.59-, same configuration, same place, same proportion of WiFi/data), I can confirm that version 21G101 caused an important battery drain, while build 21G93, which I installed afterwards because of this problems, is giving me a very good battery life, comparable to iOS 16.
If you want more details, all the tests are
in the iOS 17.6.1 thread.
If you’re interested in a stable, polished and efficient build, at least for A15 devices, my recommendation is to manually clean install (restore) this 21G93 build.