I'm not sure how true that is...I'm not clear if the modern workplace has ever been the primary source of relationships.

Places of worship, community spaces like libraries/clubs - sure...but I had to develop these skills years before I moved to remote work.

According to Google some 20% of marriages began at work, and some 50% of people say they have a close friend at work. IDK about it being a primary source, but it's definitely an important one. And it makes sense when people are around each other all day.