Exactly. The location of some shows are very important to the show, Orphan Black isn't one of those shows. It makes it relatable to anyone in the northeast part off North America.
But that is not why they do it! As I keep saying, it is not a new or unique practice -- it's been routine for Canadian-made shows sold in the US for a long time. It's got nothing to do with Orphan Black specifically. It's about the fact that Canadians have a hard time selling their shows to US broadcasters if they're overtly set in Canada, because Americans are perennially uninterested in anything that isn't about us. Why should a show have to be set on this side of the border to be "relatable" to Americans? Is Canada such an intractably alien culture? Of course not. The whole reason it's even possible for Canadian shows to pass as American is that the differences are minor. But unfortunately, even those minor differences are more than many American viewers are willing to accept.
And a show's location doesn't have to be essential to the story to be worth mentioning. It didn't particularly matter that Mary Richards worked in Minneapolis or that Mork from Ork landed in Boulder. That detail wasn't essential, but there was still no reason to hide it, and choosing a specific location allowed the setting to have more texture. Given that Orphan Black actually is set in Toronto, given that this fact is confirmed repeatedly in various onscreen documents and production details, I don't see how it would hurt the show's storytelling any if it acknowledged that fact a bit more openly from time to time. And it surely would if it weren't for the business difficulties of selling overtly non-US-based shows to US networks.