Toroidal transformers in separate power supplies ...why?

This question is not about the perennial topic of transformer hum caused usually by DC on the mains, but more fundamental, and for people with technical knowledge out there:  Why does Naim use toroidal transformers in their separate power supplies?

I do not have great knowledge of different transformer designs, though I have long been aware that toroidals have a significant advantage of reduced stray field compared to E-I transformers, particularly relevant when in close proximity to sensitive electronic circuits, and also with reduced size and low profile they lend themselves to sleek cases. I have always taken that as the end of the story - however something I have just read suggested another difference of which I was unaware, namely that toroidal transformers have much higher transmission bandwidth, and that by comparison an E-I transformer acts as a filter, so acting to reduce interference from the mains giving less to be filtered out later - and that would seem to be a good thing. So, when in a separate box where stray fields can be physically removed much further from the sensitive electronic circuitry, why not use E-I transformers instead of toroidal, even if it would dictate a different shape to PS boxes (maybe twice height and half width, still fitting a pair in the same overall space as now but side by side)?