I've just skimmed this, so sorry if any of these points are covered already.
(1) On the moral uncertainty argument: I think people tend to overlook the fact that abortion can be morally obligatory according to utilitarianism. If having a child will divert the time and financial resources of people away from more effective causes then, especially if we consider the expected far future impact of those resources, someone can be strongly morally obligated to have an abortion. In general, it seems like utilitarianism is going to tend to have pretty strong recommendations either for or against abortion in a given case, depending on the particulars of that case. In cases where someone is morally obligated to have an abortion according to utilitarianism, we have a case of disagreement between moral theories and not a case of moral dominance under uncertainty. I still think that it means we should think that abortion is worse in most cases than it is typically considered, but it seems worth noting that this isn't a simple dominance case as is sometimes assumed.
(2) On the QALY assessment of abortions: People have mentioned that this sort of calculation seems to entail that women should consistently get pregnant and adopt out the children throughout their fertile years. One issue here is that it's the additional QALY benefit or loss of having children compared with what the person would have done that should be considered when we try to determine how morally good it is for people to have children. And it seems like a lot of people have the ability to move more QALYs with their resources and time than would be created by having children (either by giving to effective causes, or by convincing or paying someone else to have a child). I think it's very implausible that EAs should have children instead of using those resources elsewhere. Of course, it's less clear in the case of non-EA people. But then I think "if you're not going to spend your money and time more morally, then you're morally obligated to have children whenever they are able to" is a view that it would probably be damaging to publicly endorse.
(3) We might be worried about how the moral uncertainty argument applies in other cases. For example, homosexual acts seem to be mildly morally good on utilitarian views, but according to a lot of religious moral theories, homosexual acts are very morally bad (and very few moral theories say that they are morally good to the same degree). Does this mean that homosexual acts are a potentially prohibited under moral uncertainty? Perhaps not, but it seems worth noting that using the moral uncertainty arguments to argue against acts like abortion might lead people to this kind of example, so it's worth having something to say about them.
I don't think this is a fair restriction on commentary for this sort of article, especially since you go into the example in such detail. You're suggesting that having EA beliefs seems to imply a higher degree of belief in the immorality of abortion than some people do have. People can respond to this by (a) retaining their abortion beliefs and changing their EA beliefs, (b) retaining their EA beliefs and changing their abortion beliefs, (c) retaining their EA beliefs and their abortion beliefs and rejecting the consistency requirement, or (d) retaining their EA beliefs and their abortion beliefs and rejecting the entailment. I don't really see why we should prevent people from defending (d) here.