An excellent (sarcasm registered and understood, BTW) point.
I am a practitioner of BDSM[0], which is, in some circles, quite controversial.
Despite the fact that my activities are always consensual and never cause harm to anyone, if my employer, clients or others with whom I have unrelated interactions with had negative ideas about such things, I could suffer serious repercussions.
I generally don't discuss such things online (or offline, if those I'm around aren't trusted), but if I did (as I am now), forcing me to link those discussions with my "legal" identity, could inflict real damage on my life -- even though nothing that I do is illegal or harmful.
As such, Vangelis is 100% correct. My private activities, unrelated to my work, are none of my employer's (or anyone else's) business, nor is it a danger/threat to anyone. If I didn't have the veil of pseudonymity here, I would never even hint at it.
And that's the problem with de-anonymization.