You say this however I went from a 2600K with 4c/8t to the 9700K with 8c/8t and decided it wasn't much of a step up, so picked up a cheap 9900KF with 8c/16t. Something just didn't really sit right with me. I think you would probably miss the extra threads if you downgraded, although chances are you'll be able to skip threadripper and just get a normal Ryzen with more cores / threads when you do next upgrade.