Do you mean the actual packaging of silicon dies and putting them into DIMMs? Yeah, they had to revert back, but that's because a lot of the memory silicon that's only good for DDR4 never shut down, and any silicon memory that is good for DDR5 is also getting claimed up for non-DIMM memory (e.g., memory packaged with logic chips rather than sitting on its own package in a DIMM or even soldered to the board).
Basically, previous generations' silicon fabrication tech is still going, and there are still buyers of that last generation product.
I don't think government funding can actually offset the crash in consumer and business demand being insufficient to cover the cost of the most expensive models on the most expensive GPUs. But if you look through my comment history I've made the comparison to supersonic flight, because I genuinely believe there's a possibility that governments fund the expensive branch of this technology for their own military or surveillance or law enforcement purposes without the benefits necessarily actually spilling out into normal commercial applications.
We've hit the point where training a model (both pre training and post training) isn't the expensive part, and the expensive part is actual inference, which makes it hard to scale the most expensive models to where it's useful for a lot of people. So it might be that the companies and governments that can afford to operate an expensive model might be the only ones to do it. And they'll be able to, without necessarily the public being able to have access to the same tech.