This isn't even true in the post you quote.
Floating ASIs incentivize non-traditional builds (as with the halforc wizard) and reduce biological essentialism. Both of those are good outcomes, from my point of view.
Re: Half-orc wizards- again, the only reason that +2 makes a difference is for optimization purposes. If the draw of a half-orc wizard is to play against type, the fact that the +2 is elsewhere shouldn't bother a player.
As far as biological essentialism goes, that gets tossed around a bunch and people seem to use the term in different ways, some of which are a bit of a soft accusation of racism; but I do believe that by having set-by-race ASIs you help reinforce the ways that race is different from the baseline, which is human (at least in my game).
I also think you close a lot of design space by having floating ASIs. What about races with more or fewer starting bonuses and even penalties? In my game, for instance, one potential player race is the kercpa, a squirrel-person that's Tiny; and its starting stat adjustments are Dex +4, Cha +1, and Str -6. Another is the dakon, a smart gorilla; it gets Str +4, Dex +2, Con +2, Int +2, and Wis +4; then a bit more for a subrace!
Both of these are examples of races who only come into play in special circumstances, and their stat adjustments make it clear that they are physically weaker than humans in one case and generally stronger, tougher, and smarter than humans in the other.
Can they be used to optimize? Sure -- but optimization happens regardless, and floating ASIs have not opened floodgates of hyperoptimized builds. At best they allow players who want different race/class combinations to not be obviously behind traditional builds.
None of those not-obvious builds are hiding. You don't choose a class-race combo, you choose a class and a race. You can choose such that you get the racial bonuses best suited to your class, but there's nothing forcing anyone to, and moving those bonuses just to be better suited to the class you choose is exactly what optimizing is.