Sorry, what? First Gen CPU's? The socket has no effect on the performance of the silicon inside. They are coming from a 12nm I/O developed over 5 years ago, to a 'new' I/O die on a smaller node. My 5600G runs 2200MHz IF, that's a 7nm monolithic design so not really indicative of how capable a separate I/O die could be.
Let's also not forget AMD are moving fully from IF to IA (Infinity Architecture) with Zen4, I'd hope it comes to the enthusiast desktop I/O at the least, given how much impact it will have with the GPU tie in.