There is a difference between "water cooler/coffee" as compared to going to a "coffee shop". When I read the article I thought "water cooler/coffee".
I'm regularly asked to "go get a cup of coffee" which is a two-minute walk down the hall to the Keurig machine and we end up talking about family, sports, etc. If another colleague were present, I would have no problem asking a female colleague if they wanted to "get a coffee" with us. For me it would be socially awkward if it were 1-on-1. And I wouldn't dare ask a female colleague to a coffee shop.
Just adding another data point — I've gotten coffee outside of the building (at a cafe) alone with male colleagues, both multiple and one-on-one, and it's always been fine.
I'm regularly asked to "go get a cup of coffee" which is a two-minute walk down the hall to the Keurig machine and we end up talking about family, sports, etc. If another colleague were present, I would have no problem asking a female colleague if they wanted to "get a coffee" with us. For me it would be socially awkward if it were 1-on-1. And I wouldn't dare ask a female colleague to a coffee shop.