Here's the QVL list for your Asrock x570 Steel Legend and specific CPU (which is a Vermeer):
https://www.asrock.com/MB/AMD/X570 Steel Legend/index.us.asp#MemoryVM
You'll notice the fastest 32GB stick of RAM they tested with was only running at 3000Mhz. and most of the 32GB sticks they tested at 2666Mhz and those were all for well known RAM manufacturers.
A 32GB stick of DDR4 RAM will be at least dual rank and maybe even quad rank, either of which will limit the highest operating frequency. As far as performance goes, you should go back to your 4x8GB DIMM config because now you're only using one channel of your IMC instead of both (HWiNFO64 reports channels as being 1 in the memory timings tab which is not good for performance). 8GB DIMMs are much easier to run at higher frequency than 16GB or 32GB.
I think you should go back to using 4 x 8GB sticks because you would get better performance.
HWiNFO64 also indicates the highest operating frequency for your RAM is 2666Mhz. NOT 3200Mhz (look at the motherboard tab of HWiNFO64). Try reducing the RAM frequency to 2666Mhz and use the timings reported in the motherboard tab of HWiNFO64 for 1333 (which is clock doubled to get you to 2666Mhz.).
I still think your RAM is the issue, especially considering you're using a no-name brand that has a 3200Mhz. sticker but the SPD chip states the fastest speed is 2666Mhz.