The B550 series is a power reduced cost cutting version of the x570 boards. They are only meant for the 6 core version of chips, and the 65W versions. You need to pick your components carefully.
VRM is the component that you need to be looking at regarding the power delivery for the CPU. There are many motherboards that combine a lower-tier chipset and a high-end VRM.
B550 was that limited initially. Even the Ryzen 9 5950X runs on B550 series motherboards today. B550 is a bit scaled down, e.g. no PCIe 4.x lines, just 3.x, but that's OK with me.
My motherboard is an ASUS ROG Strix variety with 4x32GB ECC RAM and the Ryzen 9 5950X works just fine.