That does not necessarily involve being overly paranoid and outright spying on all of their communications.
Are you saying a parent has no right to "spy" on anything their kids are doing? That's very naive . . .
Now you've excluded anyone who doesn't do so as a "good parent." No True Good Parent would tell you otherwise.
Unfortunately there are also bad parents in this world to go along with the good ones . . .
What metric are you using to determine what a true good parent is? One that sees things the way you do? Which is obviously to allow the kid to do what they want and hope they make the right choice on their own?
Because many people seem to be, in my opinion, going overboard. They're paranoid of everything and desperate to block anything they don't want their precious children seeing based on what appears to be nothing. For the children, of course.
If going overboard = me poking my nose into my daughters' lives then I'll gladly go overboard. If being paranoid = me attempting to keep them innocent and sheltered from what I deem to be inappropriate material for their age then I'll gladly be paranoid. Kids grow up fast enough today. No need to make it happen any faster.
Since I find it highly unlikely that they'll actually be affected in a negative way by the content, any age. Unless the parent has determined themselves that this specific child is negatively affected by the content. It seems to be assumed most of the time.
What if I find it very likely that my child is affected in a negative way by this content? Based on what you've been posting most parents aren't smart enough to make that determination . . .