But not an explanation for MSFS deleting itself (all content except base game) off of Xbox, after SU12 became final.
There was another thread that mentioned Windows Defender (on PC) was flagging MSFS itself as malware, so maybe on Xbox there is something similar and the Xbox OS is deleting MSFS? No idea, I just know that consitently, Sim Updates completely break the ability to use MSFS on Xbox, for me.