Strictly spoken it is supported, if you really want it you can do it. BCLK OC is a thing with 5800X3D and yields a few hundred MHz extra.Not saying they would be faster, but it would be nice to see them on the chart since overclocking is a feature that is not supported on the 3D while it is on the other two, and especially since they didn't do it with their 12900K/S review either.
12900K on other hand, who in their sane mind is overclocking that hot and inefficient mess even further? It’s already auto overclocking itself since Intel wanted so hard to beat the 5950X (which is still faster in a lot of applications and way more efficient).