are they going change their interpretation of something because John in Brooklyn questioned it and had a strong argument?
Strawman - it's not about JWs not changing their dogma to fit your belief, but you being DFd, losing all your friends and family because you questioned it. Of course some cults also do that and even worse, but the majority of the esatblished religions will not kick you out because you disagree. Even if you do leave because your world view is just too different from theirs, you will still have no repercussions because of your choice.
The correct approach was formulated by a protestant theologist:
"In necessariis unitas, in dubiis libertas, in omnibus caritas" - "in necessary things unity; in uncertain things freedom; in everything compassion".
To JWs there are hundreds, if not thousands of "necessary things", and there are virtually no "uncertain things" - the so called conscience matters are usually a joke, and they are either a way of more control (just TRY and do what your conscience tells you, and you'll see...), or they really don't matter. If dogma changes every couple of years, then by all means it fits under "uncertain things", and there should be freedom in believing it or not. The necessary things are the ones that are rock solid, and never be subject to new light (examples: the existence of God, Jesus as His Son, and the saviour of mankind, etc.)