"Common advice was always to avoid talking about politics and religion or anything else controversial in places you need to get along."
This is much more restrictive. For example, in meatspace, you can avoid talking about religion and politics at your workplace, but talk religion in your church meeting and talk politics with other supporters of the same party.
Social media tear down the distance and compress the entire world into one single space. Unless you want to avoid any religious and political discussions completely, your comments on those topics, even in specific discussion groups, can be viewed by, say, your coworkers.
Yes, because this is an unfamiliar and hard to grasp form of communication. Social media feels intimate like a home chat by the fireplace - at least sometimes. But in fact it is wide open, including to people who want to harm you.
This is much more restrictive. For example, in meatspace, you can avoid talking about religion and politics at your workplace, but talk religion in your church meeting and talk politics with other supporters of the same party.
Social media tear down the distance and compress the entire world into one single space. Unless you want to avoid any religious and political discussions completely, your comments on those topics, even in specific discussion groups, can be viewed by, say, your coworkers.
I would say that this is quite a problem.