If you cannot make the components array editable in the detail panel, consider changing the CreationMethod of your components. Here’s an example:
MyComponentArray.SetNum(2);
MyComponentArray[0] = CreateDefaultSubobject<UMyComponent>(TEXT("Component1"));
MyComponentArray[0]->CreationMethod = EComponentCreationMethod::Instance;
MyComponentArray[1] = CreateDefaultSubobject<UMyComponent>(TEXT("Component2"));
MyComponentArray[1] ->CreationMethod = EComponentCreationMethod::Instance;