In the book "On the Edge: the Spectacular Rise and Fall of Commodore" by Brian Bagnall, he writes that Atari didn't want Jay Miner to design a computer around the MC68000 processor since it cost $150 per unit, the management couldn't envision that it would become cheaper.
That's why they founded HiToro to build a computer for tomorrow. As Jay Miner was sure that both the MC68000 and RAM would become cheaper.
For the retro scene, I'm sure this will be the case too. FPGAs will become cheaper. So the MiniMig that Dennis designed will see it's FGPA drop in price. So too if someone made a 020 based FPGA accellerator for the A500.
Now, if someone sufficiently skilled has the time and motivation to pull it of... now that's a completely different matter...