I wonder how much of this "change of heart" has to do with the lawsuits brought against governments who want to yank funding from the WTS based on its previous claims of exclusivity?
If they say that all religions are worthy of kindness and tolerance:
#1 - they probably get pinkie points from governments for not (openly) inciting hatred of other belief systems;
#2 - they make themselves look like decent human beings;
#3 - it may attract more people, and conversely, retain membership which has been hemorrhaging for the last couple of decades;
#4 - there is no incentive to Witness™ anymore (why bother? if they're all worthy of Jehovah's Kindness™, even Satanists deserve tolerance)
To me this all smells of trying to keep the governments from yanking per capita funding from their bleeding coffers.