It is definitly not caused by a subscription that has ended as many have the problem with an active subscription (XGP ultimate for me). Multiple posts so far have reported that deinstalling some store apps fixes the problem. For some it is Halo Master Chief Collection for others it's Flight Simulator and I guess there are other games causing this too.
I bet it's caused by some stupid try to implement some DRM, which makes the store the worst of all software shops. The only one more restrictive is the Apple App Store but at least that doesn't crash the whole system, which makes Microsoft Store worse. The only reason I am still here is cause I bought 36 Month of Game Pass -_-".
As uninstalling all games is not an option for me, I stay with my workaround a few pages back (Page 3). Stopping the StorageService when I shutdwon the PC and starting it after the login. Note there is no need to keep it off. That will make Windows Updates impossible!