I mean... yea.. but I imagine if you can cough up the price for that kind of ram, you can already pony up for an HEDT setup... and potentially even a Blackwell 6000.
Now if you're already there.. Running a Xeon 32+ core setup or EPYC 64+ core setup and you want the greater density for your work... probably in AI these days... then the cost of that greater density becomes less of a hurdle. And the performance gains to your overall throughput is where the money really is. (edited to add... but wat this isn't even ECC... it's trash for HEDT. I fail to see the consumer for this... other than someone chasing the moar = better boat.)
The question here really is... that's great for High end consumer setups. But I think the cost to benefit ratio is going to miss the boat here..
256 gig of ram is neat... don't get me wrong. But the folks that would want that probably are better served going HEDT and 2TB of ram or clusters of the MAC mini's.