When you want to build a new cruncher you are currently faced with the choice to go for the trusted, proven and cheaper AM4 platform vs the new, unproven and expensive AM5.
Or, when you have plenty of cash, you might consider a choice between the trusted, proven and expensive WRX40 platform vs the completely new, totally unproven and very expensive TR5.

Boy oh boy, what to choose? Remember we're only in it for the crunching, so RGB does not come into our considerations. We want solid performance, some overclock potential, steady VRMs and M.2 NVMe slots with PCI-e 4.0 x4 -at least. And plenty of fan headers, too.

So: out go the A520 and (most of the) A620 boards, as they offer 'only' M.2 NVMe slots with PCI-e 3.0 x4 -and sometimes even PCI-e 3.0 x2. The 'A' chipsets can't be overclocked either, and generally have lesser quality VRMs.

The 600 series of chipsets differ from the 500 (B550 and X570) series as they fall apart in four: B650, B650E, X570 and X570E.
The E or "Extreme" branding is a guarantee that PCIe 5.0 is supported on both the motherboard's graphics slot and NVMe slots. E models provide access to all 24 PCIe 5.0 lanes from the processor. Non-E models only support 8 PCIe 5.0 lanes on NVMe slots while the rest of the lanes on graphics slots are dropped to PCIe 4.0. That's nice to know, isn't it?

To be continued/upgraded....