x570 taichi

3600 MT/s is not officially supported by AMD, this is considered an overclock. Most Ryzen 3000 CPUs can hit 3600 with 2 sticks, but it's not guaranteed. If it won't work, you can decrease the frequency to 3466 (1733), 3200 (1600) etc. The performance hit is not that significant outside of synthetic benchmarks.

Early engineering samples of X570 were T-topology, but the production units appear to be daisy-chain.
https://www.youtube.com/post/UgwjG8OxnKAGLMUVyQB4AaABCQ
I have X570 Taichi, but I didn't remove the back cover to verify the layout. The guy running AHOC channel does a lot of memory overclocking, he's trustworthy in this regard.

Single rank sticks are easier for the memory controller to drive, so they have higher OC potential. But dual rank sticks offer very slight performance advantage over single rank at the same clocks because the controller can issue a command to the 2nd bank while waiting for data from the 1st.
32GB sticks are dual rank, there's just no way to get this capacity on single rank with current memory chips.

I have 4x16GB dual rank 3200 MT/s rated sticks running stable OC at 3600. I had all 4 sticks posting at 3733-3800, but not stable for daily use, not with 1:1 FC ratio.

These are all arguing minor details around the edge of performance. I am confident the Taichi can achieve 3600 stable overclock with any reasonably competent memory kit. My X470 manages 3733 easily, and the X570 goes far higher in its published specs.

Again, just my opinion. The apparent difference in desktop performance is hardly noticeable.