Dying to switch my 3570k, it's holding back my vega 64. Tempted to get a 2700x but think I'll wait for 3700x, will they work with current AM4 boards? Would it be safe to buy a board now?
2600K (with a huge clock to be fair) to 2700X was a sidegrade (mild upgrade) for gaming (not saying I regret it in the slightest, been a wonderful rig). Amazing everywhere else, benchmarks look mighty impressive. Not... particularly skull shattering on the gaming front.
If you have a productivity reason for 8c/16t, absolutely go for it.
If you really can't wait and have to buy something, sure, a good crosshair VI X470 will be a worthy companion for the new gen.
If you can wait though, the new gen boards have PCie 4, (probably) more power phases and likely will enable an additional trick or 2 in the new chips.
I'd hold if you can help it.