I’m not so sure we sort by skin color per se; I don’t see a lot of south asians (Indian subcontinent, e.g.) self-identifying with “black” as a SIRE group, and in fact there are sub groups in modern Pakistan, (Siddi, e.g., who do identify more closely with recent african ancestry among their equally dark-skinned fellow Pakistanis). There is something besides skin color…
As for Australians, I believe the current thinking is that at the M-N split, a very early group migrated along the coast of India and eventually made it to Australia; the aborigines there are a fairly old line. If the group(s) that came out of africa evolved different genes subsequent to M splitting off, then the expectation would be that early splits who had already migrated away would not share those genes and might well end up identifying more closely with an ancestral population in africa. It all depends on which groups got what genes as evolution tinkered with them.
Within africa, the only reason to group all (sub-saharan) africans together is that they are all L3 or earlier (pre M-N), so as a group they aren’t going to share post M-N genes in their pool any more than post M-N groups would share in sub-saharan genes that developed after L3.
I completely agree it’s silly to try and divide “races,” and silly to pretend haplogroups within africa are particularly similar.
But as I mentioned, the discussion at hand is about average gene pools driving average differences, and regardless of how strongly one might oppose genetically defining a “race,” there’s no debate at all that average gene pools for self-identified SIRE groups cluster, and cluster for two reasons: First, some gene variants created by evolution achieve high penetration suggesting reproductive advantage and driving up the frequency of that gene variant; and second, historic migration patterns have separated broad groups long enough for those genes to evolve, penetrate, and alter average gene pools.
The egalitarian insists–on faith–that evolution affects only genes for “superficial characteristics.”
There is no debate, as far as I know–that the average gene pools of SIRE groups are different. This is why the “races don’t exist” argument fails. The argument for genetically driven differences is not that races exist (this is a semantic question), but that average gene pool differences exist, and because no nurturing influence has been found to erase outcome differences, then the residual difference might plausibly be ascribed to genes.