"Those" refers to the "DPM" to which you refer, and I'm just asking which of your favorite MCU's has an internal dual ported memory to which the "loader" would have access so your MCU could do the rest of the work and keep up with the pixel rate?
where do you get that I was talking about an internal DPM?

Once you find you have to add complex hardware, it's not so likely you'll be able to justify an MCU for the subordinate tasks. It's easier, particularly with video display circuits, to do that in programmable logic.

if, in the particular case, it is 'easier', it would be outright stupid not to do it that way. I presented an option which, in some cases, may be 'easier'

Erik