Congratulations, David K.  I believe you are open minded.  At least you have acknowledged that the WHO does support water fluoridation.  And of course the WHO would not endorse a practice that is unsafe or ineffective.  So, thankfully, we can put that nonsense behind us.  

But nowhere in any WHO statement does that organization limit its endorsement to non-industrialized nations.  If you can show me something I will gladly take a look.

Now to those graphs.  New Zealand scientist Dr. Ken Perrott took a close look at the WHO data Chris Neurath drew from.   

"Neurath covered up evidence for the benefits of CWF by simply using the mean of fluoridated and unfluoridated areas for countries like Ireland and New Zealand."   However, when Dr. Perrott looked at WHO data from fluoridated & non-fluoridated areas of Ireland the results were completely different.  
Have a read: 
https://openparachute.wordpress.com/2014/12/08/cherry-picking-and-misinformation-in-stan-litrass-anti-fluoride-article/