You could be right tbh. They’re probably experimentingSeems like Apple have made some modifications with 11.2.2 regarding slowing phones down, like 6s. My 6s has a not so good battery (2 years old). My 6s was affected by the very well know syndrome of slowing phones down to solve battery problems by making the hardware slower.
Now, with 66 prcent battery, my phone died. Which is just as Apple said it would happen without the workarounds
I also read that other people are complaining about ”real bad battery performace with IOS 11.2.2”.
For me it seems like Apple somehow has decided to stop slowing phones down. Maybee not in full, but with a compromise, and that could be why people are experiencing sudden shut downs and draining batteries with older iphones on IOS 11.2.2.
-Just my speculation.