They aren't dead. And no, it is not quite clear they will close. Anything can happen in the next year or two.
Even if they do close up shop under this ownership, there is nothing to suggest another company won't take over their PSU and other component lines.
The owner has already made it clear to those who asked him that he's not interested in selling. Supposedly he didn't want to see the brand he helped create turn into something else out of his control. The Nvidia thing was the biggest nail in the coffin as he's looking to retire and spend more time with family, so a soft-ish exit for the company is what's currently under-way. There are no contracts preventing them from going to AMD or Intel. Just the owner's sense of "honor" in not wanting to betray what he felt was built between him and Jensen. If they were going to make AMD/Intel GPUs, they would have by now.
Also, they didn't make their own PSUs or peripherals anyway. All PSUs were FSP, Seasonic, or Super Flower (for the older ones), etc. As someone who owns their best keyboard and mouse, I wouldn't recommend them. They've been buggy, lacked proper software support, defective, and waaaay overpriced. They used to make excellent PSUs (I've owned several), but they've been very hit or miss since "breaking up" with Super Flower. I still have the z690 Classified and I do really like this board, but there are still BIOS bugs that'll never be fixed. I'm currently running the first non-EVGA graphics card I've owned since my XFX 7600 GT. I'm trying to make clear that I've been a fan of theirs for a long time so I'm not happy to say this, but unless something drastic happens, they can't sustain their current path.
Also, it is not currently clear that they're still making motherboards. They may have just been clearing out all their inventory (save for RMA coverage) as they haven't been in distribution for a little while.