Welcome asprin.
In the early days, Russell and others ATTACKED the Catholic church in particular, though all "organised" religion was also the target of his wrathful public discources. The feelings held for the Catholic Church ( one could say the hate), continued through the decades, and maybe down until today. I haven't read any WT publications for 15 years, but a guess that their remarks towards the church are the same.
I think it would be fair to say that most JWs are ex-catholics. (large numbers in strong Catholic countries)