It has nothing to do with puritanism. If project leaders don't set good examples, people "lower down" in the hierarchy will also act like jerks, and the project will lose potential contributors as a result.
Anyone who depends on, or is invested in, the security/stability of the Linux kernel, or cares about such a reputation. Which should include core devs.
It's not clear to me he is a jerk. If LT only shouts when things are important, people without important tasks have no reason to shout.