Android 7 (Nougat) was released to the general public in August 2016.
Six years later and right on cue Android 13 has just been released. At this point Nougat has not received a software update in four years as it is no longer supported by Google. Latest and last security patch was on October 2019.
In order to accommodate support and testing on new versions of Android and take advantage of newer APIs we have to drop support for older versions. We already are having most of our users on Android 13 therefore we will soon be increasing our minimum API level from 24 (Android 7) to 26 (Android 8).