Personally, I think we absolutely should. We know of genetic defects that cause disabilities and by leaving them there through deliberate inaction we essentially inflict a disability on a child. We also prevent potential advancement of our species.
Cost is a terrible reason to prohibit this and your argument can be applied to nearly all other medical procedures. They all cost money and sometimes that makes them inaccessible to people who need them. This is a different problem to genetic modification.
As for your article, going through the "cons" section, it mainly raises things that need to be thought about rather than reasons not to do it. My opinions on a few sections:
- "making irreversible changes [to people and] all their descendants would constitute extraordinarily risky human experimentation": The changes are only irreversible to the first generation, the same process that introduced the change can removed it in the offspring. The change being irreversible isn't alone a good reason to prevent it. Again, there's precedent for this in existing medicine. If a limb or organ has to be removed, that certainly isn't reversible. If there's a choice between my child definitely being born with a known defect and a child maybe possibly being born with an unknown one, I'd likely take the latter. However I do believe we should understand things better before we go making frivolous modifications to hair colour and such without understanding the consequences.
- "By definition, germline gene editing would not treat any existing person’s medical needs": You're going to refuse to treat someone simply because they're not born yet? Again, acting through inaction. The same benefits brought by treating infants are brought by treating them before they exist.
- "Would germline gene editing be justifiable, in spite of the risks, for parents who might transmit an inherited disease? It’s certainly not necessary. [...] They can do [PGD] too [...]": PGD and CRISPR differ in process but as I understand it, not in result, so I don't believe you can say one is okay but not the other. As for the other section here suggesting you can use third-party sperm or eggs, yes, you can. It isn't strictly necessary to use gene modification techniques if you're happy having someone else's child but it still amounts to selecting for desirable traits.
- "PGD itself raises social and ethical concerns about what kind of traits should be selected or de-selected. These questions are particularly important from a disability rights perspective (which means they’re important for all of us).": I'm not sure I quite get the disability rights perspective. I believe this only really applies to people who believe that life begins at conception, who would argue that selecting candidates that don't have a disability over ones that do amounts to some kind of genetic genocide. Personally I don't buy that. Why should we leave things to chance when we can give the parents the choice to do what they think best for their child?
- "From a policy perspective, how would we draw the distinction between a medical and enhancement purpose for germline modification? In which category would we put short stature, for example? We know that taller people tend to earn more money. So do people with paler skins. Should arranging for children with financially or socially “efficient” varieties of height and complexion be considered medical intervention?": Again, there's precedent for this in existing medicine. Treatment for things like dwarfism and albinism are covered as medical procedures while treatments for mild sunburn and not being able to reach the top shelf are not.
Ultimately the article raises a lot of things to think about but I don't believe any of them are good reasons not to pursue genetic modifications to humans at all.