This would better explain why Lockhart may exist and why it may be around 4TF. If Pro is going to become the 'base PS5', it's going to be a 4.2TF console for $299 by that time most likely. If MS sticks with XB1X specs, it'll be at least $349 if not $399, which won't be good for them up against a cheaper PS4 Pro that works with the PS5 ecosystem. You would have to assume in this case that Lockhart would have at least 8 cores, 8 Ryzen cores probably, but if it happens to only have 4 or 6 Ryzen cores, a casual will see the 8 core Pro and very well may assume it's better because more cores, which wouldn't be good for XB either.
I'm not so convinced that all cross gen games will necessarily be 30fps. If they are already set at that on PS4, then sure, they will stay that way even on PS5, but for the PS4 games running at 60fps, I think they will remain at that as well on PS5. What we may see is that with new upcoming cross gen games, the PS5 version may be able to play full 4k/60, while the PS4 version will be 900p/60, and Pro being 1440p/60.