This isn’t about Sony “relenting”, Arrowhead needs Sony’s PSN support network to deal with support tickets: it’s the whole reason Arrowhead signed up with a publisher instead of self publishing and developing an international workforce of support agents. I hate Sony as much as the next person but let’s be honest, Arrowhead needs Sony and PSN, and it makes sense given they want to spend their time making games rather than getting into being a publisher and help desk.
Ultimately, Arrowhead should have made it a day one requirement and delisted the game on Steam for every country that lacks PSN support. Instead Arrowhead and Sony decided to let it ride and enjoy the sales and accompanying popularity.