They were in full control of the chipset, so it would have been easy, just the solution I mentioned is not trivial.
They always thought along the lines of how the sw people make c2p work and replicate that in very cheap hw, instead of doing an easy and dedicated hw mod.
Turning off p2s hw does not involve anything off the shelf, just gating a few lines, plus some logic.
A framebuffer could be off the shelf, and was very cheap that time, they did not do that either.
They simply did not see how big this hw gap is going to grow, so they ignored the demand almost completely.