During the early stage of my research career many years ago, as a graduate student, I met this young and bright but yet very manipulative PhD student. Let's call the person A.
At the beginning A was cordial and told me to work on the same type of research as them. After I decided to carve out my own path, A for some reason either decided that my focus was not as esteemed/prestigious/intellectually challenging as theirs, or that perhaps I am not cut out to be a researcher, so A took every opportunity to mock my research focus in front of other senior students in the lab. I cannot delve into details but at that time I saw all the signs of A being a sociopathic bully or at least an elitist.
For example, A would probe me and other students to see if we have some deficiency in our knowledge. Afterwards, A will make a huge deal out of it.
A also has unrealistic high standard for work that they imposes on everyone. Anyone who doesn't conform to their schedule would be openly mocked or even socially ostracized.
A has this very inflexible way of deciding who is worth talking to and who isn't. A will respect anyone who has a big name and deride people who are junior to them.
Because A was productive, therefore my then supervisor tolerated A.
I recently found out that A is becoming a professor at another (better ranked) school. Is there anything that anyone can do at this stage to prevent a jerk from becoming a prof?