The X570 board has the "older" (significantly slower) WiFi chip.
I have used both series and would clearly recommend the B550 or one of the new X570S boards. Here the difference is very clear, around 150Mbps net with the X570 and 500Mbps net with the B550 (access point provides a gigabit connection).
MSI's data sheet describes it exactly; I think 433Mbps vs 866Mbps vs 1.2Gbps or similar.