WSL2 has better performance for accessing files in the WSL filesystem than WSL1 does (partly because the WSL files are stored differently).

But it has worse performance for accessing native Windows files than WSL1 does.

In any case I think an assertion that WSL2 has no performance issues needs a serious citation (as opposed to no citation which you gave) - you're making a claim about all possible situations. As always, a statement that "no x exists" requires seriously more proof than "at least one x does exist".

That's not the full story. WSL2 has serious regressions in cross-OS performance, and many users have switched back to WSL1, which supposedly isn't going away any time soon.