I don't think it's about being 'scared' to post Pagwatch, not as such anyway.
People generally speaking don't want to sully their good MN name so to speak, if they are genuine. They don't want accusations of troll, goady fucker and their ilk to follow them round the boards.
Combined with this, most people genuinely don't wish to cause offence or distress (again if they are genuine) and so err on the side of caution.
Generally speaking I often think where something is posted is a good signifier. The thread about the OPs daughter was in primary education. I'm sorry it upset people but I also feel it was a reasonable question for someone to ask. In AIBU it might have had more of a 'GF' tone to it.
Furthermore, it could be argued that by dismissing people's worries and anxieties about posting that in itself is dismissive to a group of people. I can quite understand why people want to avoid the topic as it seems difficult to mention at all without causing offence to somebody, somewhere.
With all that being said, I don't like to think of people being upset. So I am sorry people have been.