I’m running that exact combination and it performs as I need it to. I’ve seen reviews of the Tomahawk Max running a 3950x and benching the same as a good X570, ok at stock with no OC. The Tomahawk Max has better VRM’s than some low end X570’s and unless there is a specific X570 feature I think most users are not going to benefit by going X570.
My 3700x with PBO happily runs between 4.3-4.4. I’ve also overclocked my 3200mhz CL16 RAM to 3733 CL16 using the Ryzen memory calculator.