Good question it might be just one or the other because i think both need a different pin connection.
As far as i remember each major change in different memory or IO in general sports the need for a new socket.
True about the older model threadrippers and if i look at the specs of the TRX40 i would not be surprised you probably can game on them as well
But somehow i think some games might not work on them, especially because AMD calls these machines workstations, but yeah time will tell
AMD did already made clear by being silent that their would not be compatibility between the old and the newest ones, it would surprise me if TRX40, TRX80 and WRX 80 could be interchangeable because the highest end of the market always was on its own.
Leaves the question open if the 8 channel models will be interchangeable or not.
I really would be utterly surprised if it would be possible, as far as the leaks go will the TRX/WRX 80 support up to 64c/128t but more than that is not known for a while longer.
However the massive caches on the new models might make massive difference because the AI has been enormous improved to detect what is needed before it is needed.
I sure want to see how often this AI prediction performs and how often de predictions are spot on. Because we all know that on the xeons the prediction on them is good but also often have a miss and in computer terms slows them down because the cpu has to wait for the correct data from slow sources.