Suppose we have a severe shortage of a drug that is prescribed on a "grams per kilogram" basis, i.e. a 300 pound patient needs three times as much of the drug as a 100 pound patient. Should weight then play a role in allocation decisions, such that (all else equal) lighter patients will have priority over heavier patients, or would it be more fair to simply allocate by lottery until the drug runs out?
It seems to me pretty clear that we ought to prefer to help more rather than fewer people, all else equal, even if it means that all those helped have a characteristic in common (low weight). But I expect that a lot of people would disagree with this, and automatically regard it as "discriminatory" and hence "unfair". Can such objections be rationally defended?
Such objections remind me of Harris' confused claim that the QALY metric is inherently "ageist" and "ableist". In both cases, the objector moves too swiftly from unequal outcomes to the procedural conclusion that members of the less-helped group must have been unjustly neglected. But this is simply fallacious. It's true that it would be unjustly discriminatory to count the interests of some people as less important than those of others, on the grounds of some morally irrelevant feature like age or weight. But unequal outcomes are not always the result of counting some people's interests for less. When utilitarians advocate for these unequal outcomes, they do it precisely because they are counting all people's interests equally, and there just happen to be contingent practical reasons why some people can be more easily helped than others. A morally irrelevant feature (i.e., of no intrinsic moral significance) may be highly practically relevant (i.e., of great instrumental significance) to the securing of morally worthwhile ends.
In the age case, the appearance of "ageism" results from the practical fact that younger people tend to have greater life expectancy, and so a persisting health benefit will tend to help them for longer than a superficially similar "benefit" to an older person. The duration of a benefit, while less salient than the momentary impact of a benefit, is highly relevant to how great a benefit it is. The accusation of "ageism" thus results from a failure to look beyond the immediate impact of a benefit. When we see that a certain intervention actually offers a greater benefit to a younger person than it does to an older one, then there can no longer be any reasonable objection to it. There is nothing objectionably "discriminatory" about prioritizing more-beneficial health interventions over less-beneficial ones.
The weight case is slightly different. Here the issue is not that heavier people get less benefit from treatment, but just that they require more of the scarce resource in order to receive treatment. This means that, if we want to help as many people as we can, without regard for their morally irrelevant characteristics, then we will naturally end up prioritizing lighter patients. This is not because we count their interests for more. It is just that they are easier to help -- we can help more of them for the same amount of resources. And given a choice between helping more people or fewer, we should surely prefer to help more.
To think otherwise is, in fact, the objectionably discriminatory position. If one wants to avoid the appearance of differential outcomes, then one must actually take morally irrelevant features into account -- to treat a single 300-pound person as morally equal to three 100-pound people, and hence to treat the former person's interests as three times as weighty as the interests of each of the lighter people.
This is not what the superficial egalitarians intend, of course -- they do not think of their preference for superficial equality as "discriminatory" in this way -- but it is the actual moral upshot of their approach to the issue. It is deeply morally misguided. We should not prioritize superficial equality over the more fundamental equality embodied in the utilitarian ideal of giving equal consideration to the interests of all, regardless of their superficial characteristics.