Yay! With 55 more minutes worth of “ticks” I found the solution. The idea is to register the component
RegisterComponent();
besides setting
PrimaryComponentTick.bCanEverTick = true;
Furthermore make sure to instantiate the UActorComponent in the following fashion
BrainComponent = NewObject<UMAIBrainComponent>(someactorpointer);
Then the UActorComponent WILL tick!