It also doesn't make G2A "A black market for software".
G2A is fundamentally a consumer empowering type of market/organization, businesses who sell keys do not want their completely legitimately purchased keys resold, and if you don't think they are going to stoop to painting the people who enable that as horrible monsters, you have ignored the entire history of markets and PR.
G2A has a standing offer to pay devs 10x what any fraudulently obtained keys cost them, and they are making good on that offer here, the fact they are still being treated like some kind of mafia-esque organization in these comments says a lot about the power of PR.
Remember when the RIAA was coming out about the evils of used CDs and was asking congress to make their resale illegal?
We are at that point right now with digital goods, with the majority of people cheering on this blatantly anti-consumer bullshit and painting those that enable fighting it as scumbags