Why Does EVERYONE Say Their Parents Were Bad?

I don't know if I visit the most representative locations on the internet as far as statistical samples go by frequenting Yahoo news articles and political Youtube videos and such, but I swear, in almost every forum or comment section, for every one person I see complimenting their parents and calling them a blessing, I see about 20 or 30 talking about how toxic their parents were.  And we're not talking about teenagers that are still in the middle of maturing and dealing with discipline issues.  These are people in their 30's and 40's who've had ample time to look back.  

My question is, why the dissatisfaction?  Are there really THAT many bad parents out there abusing and neglecting their kids?  Is there just too much expectation regarding parental roles where they have to be absolutely perfect to even be considered decent?  I mean, WHY do so many people have problems with their parents?  I had awesome parents, so it boggles my mind that so many people apparently did not.  

I can't stress enough that I have NO problems with my parents and what they did in my upbringing whatsoever.  They were good people that tried their very best and did WAY more than they ever should have for me.  Were they flawed human beings?  Of course.  Who isn't.  But once I grew up, and possibly even before then, I could certainly tell that they clearly had my best interests at heart and put in SO much effort and sacrifice for my own wellbeing - particularly my mom.  

This realization is not dampered when I look back and think how scared I was when my mom yelled at me or how mad I was at my dad for using the belt when I got really out of line.  They did these things because I needed correction.  Not because they were on some power trip or thought it was fun.  Because they darn sure didn't seem to have fun correcting me.  Not to mention they bought me more toys than I could even count over those 17 or so years.  And they didn't cheat on each other or spend all night at the bar.  

Are parents like mine really so rare?  If so, I guess I can see why the divorce rate is so high.  But it still boggles my mind that so many parents would be problematic enough to not even be considered decent, much less good.  

Even if I classified mine as phenomenal, that could still potentially be an understatement.  The fact is they deserve more love and respect than I could ever give them.  Thank you mom and dad.  Regardless of how your peers behaved, you were shining examples of a traditional family structure.