What you mentioned about 10105F users forced to 720p after a couple of years don’t make sense to me. As you lower gaming resolution, you are actually making the CPU work harder because the bottleneck is on the CPU, and no more on the GPU. So if your CPU is already a bottleneck @ 1080p, then dropping it to 720p is unlikely to give you any meaningful improvement in gaming performance.
CPU pricing wise, I am in agreement with you that it should go lower. However, if we consider the full cost of the system, you can pair a R7 5700X with a budget bin motherboard, and it will run perfectly fine. Conversely if you want to run say an i7 12700 at full potential, then budget bin motherboard may limit performance. There are reviews of ”cheap” Intel B660 boards but runs very badly. So if you are looking at cost, then do consider the full build cost and not just the CPU cost in silo. In addition, I feel AMD’s hands are tied when it comes to pricing since they don’t manufacture their own chips like Intel.