Longtime lurker here, and I just wanted to chime in on the possibility of the PS5 being $399:
It's probably a long shot, but Sony is also pretty strong in emerging markets where the PS4 became the default console because it was affordable (compared to Xbox One at that time), and because of regional pricing (especially on games). While they aren't as huge as the American market, I don't think Sony would price that PS5 out of their league, especially in light of them wanting people to migrate to the PS5 a lot sooner. $499 would be okay in the US/PAL/Japan, but it definitely won't sit well outside of those regions. I also don't think Sony is willing to initially put a high price on the PS5, only to give it a price cut a year later.
I can definitely see a $399 PS5, and perhaps a $299 DE (which would make some people here migrate to digital, but the majority would still choose the disc version because of our crappy internet)