I certainly expect a 5nm Series X. I do wonder if they'll keep the Series S on 7nm for cost, but I think it's more likely to also make the transition to 5nm.
Within the same generation, I think you're right that there's a good chance MS will adopt a newer uarch such as Zen 4, but I think it will be the same number of cores and the same clockspeed or greater. Current code could run without issue, but newer code could take advantage of a "free" performance boost.
I'm not so sure about the GPU though. RDNA3's something of a damp squib, unfortunately, although its mildly improved RT performance coupled with being ready to go at 5nm might make it more cost effective than porting RDNA2 to 5nm. What do you reckon there?
My guesses would be MS would make use of the latest ZEN and RDNA uarchs available when time comes for a revision, simply because they can. There will be efficiency gains, and some small performance ones, but the ultimate goal would still be to reduce costs, heat, and size.
For Series S, the ultimate goal definetly is to reach a steamdeck/switch form factor. When that's doable, I think they'll try.
If not, I see two paths for Series S:
1. keep the exact same real-world performance target but take advantage of new architecture eficiencies and node to reduce cost, heat and size as much as possible, and cut price as agressively as economically viable. Perhaps cheapening the power suply and fans significantly for thar goal.
2. Maintain compatibility with the previous series S, while reaching parity with the ONE X in the aspects its falling behind ( 6 Tflops GPU, 12Gigs of ram etc ) so it can play games at slightly higher fps/res than Series S vanilla, and play previous gen games at the Series X settings.
For the premium Series X, I don't imagine MS wants or needs to reduce price as much as reduce the size of the unit significantly. They probably will take the oportunity to close the gap with PS5 in all the small diferences it holds an edge (higher clocks, double ROPs) so the Series X Slim is hands down superior in every game in every scenario. They will take it an inch ahead of the PS5 in those things and nothing more. Memory ammount or speed won't change, nor will SSD streaming tech, audio, etc..
For both revisions, devs wont be required to make custom enhancements for new games targetting the new performance profiles. Unlike how it was done with ONE X and PS4 Pro. Games will play in compatibility mode by default, but devs will be encouraged to test games in unlocked perf. mode for higher fps and average res (for games where res is variable) and whatever other features scale automatically on each engine. Devs will be allowed to make deliberate tweaks targetting specifically the revisions, but won't be expected to.
It would not be a midgen refresh in the same scope as last gens One X, but more like how the One S was. But I'm expecting to see some small but apreciable perf bump.