It will move and will help extend the generation.
Adding more storage will also be appealing to some.
Ps4 was at 50 million units when ps4 pro launched. I can't find any figures for sales splits but the first year 1 in 5 ps4 sold were pro. It was discontinued in 2021 and the ps4 was at 116 million. So let's be generous and say that the ratio of ps4 pros went up to 25% overall, 25% of 66 million is 16.5 million. That's the optimistic figure, when you realize the base ps5 is already powerful compared to most pc's, even midrange ones, there's much less incentive for people to buy a ps5 pro.
But let's just say 16.5 million units, a 1 billion dollar tape-out would add $60 per unit -just for the wafer design-. Then you have to add the rest of the BoM. In order to get a suitable performance bump we'd likely need 7900xt levels of performance, and probably even more raytracing. Let's say we convert the extra transistors in the 7900xt that are used for double pumping FP calcs and turn them into extra RT cores to keep it simple. 7900xt is 80 CU on a ~530mm^2 die. The ps5 pro APU would need 72 CUs, or 450mm^2. Add another 60-70mm^2 for the cpu portion of the apu - we'll say it'll be comparable to a 7700x and you get 520-530 mm^2. On 4nm you should be able to get a 5% shrink over 5nm, so let's round it to 500mm^2 for a ps5 pro apu. That yields 69 good ps5 pro apus per 300mm wafer. I don't know how much a 4nm wafer costs but 5nm costs $17,000 per wafer and let's be generous and say sony/amd gets preferential pricing because of their relationship with TSMC and use the $17,000 figure. That means the APU would cost $246 each. We're already up to $300 on the BOM and we haven't touched on any of the other components. No SSD, no GDDR (which you'll need more of, with a wider memory bus, to keep all 72 CU fed - 24GB at $7-10 per GB... you do the math), no motherboard or VRM, no heatsink, no plastic shell, no controller. I wouldn't be surprised if a ps5 pro cost $600+ just to assemble. Then you're going to have to price it so that you can profit after shipping, retail cut, marketing... don't get me wrong, if it's powerful enough I'd personally pay $1000 for a pro console. But certainly not 20% of ps5 buyers would.
It just doesn't seem feasible at this point.