I suspect it is spontaneous, not that some don’t make a deliberate effort to inflame passions.
Sadly, I think it originates in a climate where scientists are accused of deliberate manipulation, fraud, and acting out of pure self-interest (ie financial), etc. This kind of rhetoric sets the scene for these attacks from a small subset of people take these accusations very literally and respond in kind.
People who frame the scienitfic disagreements in terms of purposeful malfeasance on the part of some scientists, should have a good hard think about what contribution they may be making to this problem.