Good news bad news: learning in collaboration with others via social media can be amazing when learners(and their organizations) engage.
Learning in the company of others offers learners a significant benefit. Individually they learn from gaining and applying their own knowledge. In groups learners benefit from insights triggered by others sharing their perspectives.
A traditional classroom's capacity may constrain group learning. Environmental issues might hinder social learning as well.
Learning via social media removes some of the constraints. One, with walls gone you can share knowledge with as many others as you can network with. You can leverage technology to share perspectives across a variety of media: writing, videos, podcasts to name a few.
To benefit from social media learners have to invest themselves in it. Thinking about learning as earnings they have to work at it.
Social media can be a thorny issue for some organizations. Some I have produced learning experiences for have strict policies in place on how social media can be used. Others may prohibit it completely. There are cultural constraints as well. Things people share online via social media is visible. It takes a lot of trust for this exchange to happen.
Trust is the currency of learning with social media. When the trust is there learners are motivated to share. My job is designing training that leverages story, what some might call case studies, to hook learners interests and empathy. I keep advocating for it, designing it in where I can. We're getting there.