"MMAL advanced" is borderline/too much for 1080i, therefore it's done using bob which needs fewer resources (memory bandwidth especially).
I'm not 100% sure about RPi0-3 but ISTR they had similar issues - except for test streams I don't have any 1080i content here.
RPis don't have a hardware deinterlace block therefore this is being done by software running on the videocore CPU - and that code is the same on all RPis.
so long,
Hias