The enemies of this kind of constructive discussion are words like 'always' and 'never'; basically absolutist thinking.
Things in life are rarely so simple as to be absolute, as soon as you hear people making those kinds of arguments, you can call them out on it. If they get the point, then you might be able to go on and have a constructive conversation, if they dont understand, you may as well give up; their minds are set and its unlikely that you will make much ground.
It seems to me that many people dis-like complexity, they want simple answers to complex problems, and polititians love feeding that desire. Its that kind of instant gratification requirement "We have a big problem, but dont worry I have a simple answer"; attractive, isnt it?
Its the same in crypto, we want a fully decentralized, fault tolerrant, robust consensus mechanism, that uses no power, costs nothing to use, and is instant (and probably some other things I forgot). Its a complex problem, what happens is many people latch onto one simple answer that they invest not only their belief, but their money too. Then you come along and present a slightly different answer, so clearly you are absolutely wrong, the coin that persons supports is 'always' going to be the best and can 'never' be surpassed.
Of course with absolutist thinking comes the real and present danger that you are actually wrong (you are probably wrong as its not often feasible to be right in a complex world), but such lessons are not learned, people just grasp even tighter to the 'life-raft' of their current beliefs.
I did see a concept that can be used to shock people out of this type of thinking, basically instead of arguing your point, you argue on the side of their point so extremely, that they begin to question their own strength of belief in it. For example 'Crypto-currency _____ is so good, all fiat should be immediately destroyed, all monetary equivalents such as gold, silver, artwork should be destroyed, and we should force all peoples to use ______. All exchanges should be immediately closed and no-one should be allowed to convert their fiat or other assets into _____.'. Insert the coin of your preference.
I completely agree with you, and it's important to call people out when they start making absolutist statements like that! Well said :)
Meanwhile, back in 1984....