No.
That's not how sane people react. No-one who has a solid grasp on reality hears someone call their friend, who they know is a nutcase, however nice they might, a nutcase, and then goes "OMG U CRITICISED MY FRIEND I MUST BECOME A NUTCASE 2". They might well go "Well Ruin Explorer is a total scumbag who doesn't get how kind and loving Nutcase Ted is, eff that guy, not listening to him", which is fine. But that's very, very different to "I TOO MUST DRINK THE KOOLAID!".
Only people who absolutely wanted to embrace the nutjar do that. It's the same naughty word as racism and homophobia. People say "Oh well if you call someone who his racist and homophobic, racist and homophobic, they and their friends will become Nazis!" and it's like, no, not unless they were already well on the way there, and just looking for any excuse.