Earlier quoted context omitted.
> It's "fair" if you're referring to equal opportunity, not equal outcomes. Fairness and equality are different. Imagine 2 people of different heights who can't see over a wall - equality is giving them both a ladder of exactly the same height even if that means just the tallest person can now see over the wall, while fairness is giving them each potentially different height ladders so they can both see over the wall…
Regarding your first paragraph, from Oxford Dictionary, "fairness" means "impartial and just treatment or behavior without favoritism or discrimination." The above poster was right — it's fair if you're referring to equal opportunity, not equal outcomes. I've seen this whole ladder analogy commonly used in radical socialist, communist, CRT-type Instagram accounts, used to reframe discrimination in a positive light.
That doesn't imply simplistically equal treatment. If the definition was "equal treatment" that's what it would say instead of "impartial and just".
Impartial and just and no favoritism or discrimination isn't meant to literally complain "hey, you're discriminating in favor of car crash survivors getting physical therapy, that's not fair, everyone should get the same physical therapy".
The definition probably would be better to use the term "prejudice" instead of "discrimination". There's no reality in which people see fairness in absolute lack of discrimination. It's fair to discriminate based on something like medical diagnosis or any other sort of fair judgment of situations.
The false dichotomy of opportunity vs outcomes is stupid. We can't make true equality of either, and we can care about both. And just saying that you see extremists use an analogy is not a reason to reject an analogy. Extremists also wear pants or sleep at night. Anyway, an absolutist no-discrimination view is about as extreme as we can find.