It is true that people must take responsibility for what they post online but that is only one part of the overall equation.
* Humans tend to make snap judgements of others
* Humans tend to label and box others into groupings that make them feel comfortable
* Humans have biases and fears based on a lack of understanding or a belief system embedded early in life
* Complex employment laws, human rights acts, anti-bullying/harassment and privacy legislation have come into being because of inequities commonly inflicted on others based on humans being humans.
In other words-regardless of how professional, positive or reasonable ones posts online are, there will be someone out there who will see it differently or react to an inherent bias. That reaction does not need to be reasonable, rational or fair, but it can disadvantage someone. I have read so many odd comments by people in a position to hire/not hire or affect ones job candidate status based on a snap judgement coming from a strongly held belief that I consider it to be a good reminder of why we have all that complex legislation.
Humans are humans-the ones posting and the ones looking at those postings to judge others are all inherently flawed. Because we are human. It is too easy to discredit someones competency or job worthiness based on online content-or the content of someone they are connected to, but it simply isn't reasonable to do so in many cases. And in the situation where it may be a valid concern-a bona fide occupational requirement-or the potential harm factor-the decision maker is obligated to ensure that what they think they see/belief/assume is in fact accurate. If you are in Canada a bona fide occupational requirement (BFOR) is defined at this link, although it is good advice regardless of where in the world you are hiring. http://www.chrc-ccdp.ca/preventing_discrimination/page4-eng.aspx
Which is why discussions on topics that have the potential to change our understanding of acceptable social norms is so important. And technology based social networks are changing our understanding of acceptable social norms-we collectively will be better off if we consider the angles.