Data itself is irrefutable.

On my XperiaX the batterylife has shortened considerably over time; if you check the 4 charts above and compare it to what the decay profile looked on v2.2.0.29 on June 2018 the trend is clear.

Again I stress that there are also other factors to consider in addition of the SFOS version changes; it might be that my usage patterns have changed over time or the battery of the device itself might be getting old.