Consoles are all purpose-built soldered memory configurations, so you never know what they may do. Would probably be something you wouldn't want to fail, so more likely to be conservatively robust by design. The best part of purpose-built is that you can build tighter specifications for the layout, keeping trace lengths tight. And because of economy of scale, you can build something more sophisticated at a cheaper final cost. I don't think with $1,000 phones being the norm, that a $1,000 console with 8K capability is out of realistic expectations.
Sony should steal Apple's playbook and offer $1,000 PS6 baseline and start with 'deluxe' models launched between $1,200-1,500 in various limited editions. Offer a supercharged version at $2,000 within six (6) months. Tease the supercharged model from the beginning to break sticker shock. If its really special, especially when it comes to 8k performance and load times, you goad your competitors to compete.