There's good and bad in any arbitrarily defined group of people. Try not to define the whole by the actions of one or two. Furthermore, the trauma of living as a JW and then being DFed (vs waking up while still in and leaving after, which is traumatic in itself) is enough to make some people go off the rails in their anger at what has been unjustly done to them. Is it right? Probably not. Are they acting angry/bitter just as the WT says they are? Probably. Is there a completely justified reason for them to be angry/bitter? Absolutely yes.
One of the bigger realizations that allowed me to wake up was seeing that even if apostates are angry/bitter and that drives some of their more objectionable behavior (latching on to false rumors about the organization, protesting at conventions, being insulting to believing JWs, etc) that maybe they're justifiably angry. Maybe they are bitter apostates, but if what they say is true (i.e. the cult has systematically lied to us to our detriment) then I should be one too.