The ASRock X870E Taichi wins in 9 out of 14 comparable specs, with 2 ties. Its biggest advantage is Max Memory (100% better).
B550 AORUS PRO AC wins in 3 specs (PCIe x1 Slots: 100% better).
Recommendation
Choose X870E Taichi if you want the best overall performance — especially max memory.
Choose B550 AORUS PRO AC if pcie x1 slots matters more to you.
