Emulation developers are still going back to the
original hardware for accuracy checks decades later for the regular SNES, one of the most popular pieces of hardware that is extensively documented and millions of units available out there. And they likely will have needs to confirm on hardware for a long time. If prototype software is found for the system, which is very possible to exist out there, then the original hardware is vital in that process and who has it can make that process incredibly difficult.
Yes, I'm aware. If this happens, that would suck. However, I argue that it's unlikely more software will be found or made available and that it's not "very possible" (the project didn't get very far, after all), and in the case that any did arise that did require more investigation of the hardware that wasn't too invasive (byuu talks about
decapping chips in that article, remember), I think you're being assumptious that 1) a public institution would definitely allow access to the hardware and 2) that a private collector would definitely disallow it. This set of circumstances occurring is at such a vanishingly low chance that it doesn't bother me, sorry.
The significance of the artifact absolutely matters. I don't see how you can say otherwise. There being tens of thousands of PS4 prototypes in existence is less important than having this prototype because this one is more significant, more rare, and has a much more profound impact on the industry. You keep saying because people have seen it and documented it, that it's okay for it to disappear. Why is that okay? It's one step away from someone destroying it. Would you be okay with that if someone destroyed it since it's been well documented? Think of how many artifacts that exist out there that have been well documented; are we okay with all of them being stored away in a private collection because of that fact? Your reasoning that it's been well documented making it okay to have it go away is an awful stance to have. It's not just for now but for the future as well.
It disappearing into a private collection is not "one step away from someone destroying it". Of course I wouldn't be okay with someone destroying it, but preservation =/= public access as much as either of us would like that to be the case. It's not "okay", it sucks; it's a sub-optimal outcome and it would of course be better for it to be in a museum or similar, but it doesn't affect our understanding or knowledge of the history of the console itself or the events of the industry surrounding it. If
all we had was that old magazine scan from the 90s that ended up being accurate and
just confirmation that this prototype existed and nothing else, this would be an untenable situation. But it's not.