@Zac67:
Apart from needing double as much memory, they would need double as fast memory as the pixels would be sampled at ~28MHz and output at ~56MHz compared to ~14MHz and ~28MHz now. This if they would stick to their current design and just scale it to be able to manage Super Hires.
(edit):
I also forgot that they also need a faster D/A if the separate ~56MHz pixels are supposed to be distinguishable.
/Patrik