Many new members don't know how to PM.
Others wouldn't think of it perhaps.
But it is a point.
If we see a post, we can react.
If it's PM we'd never even know.
Bet this happens anyway, sometimes.
My experience as a moderator on another (not tort related) forum suggests that PMs are certainly sent by new newbies. We have a minimum of 5 forum posts before a PM can be sent.It may be true that new members do not know how to send PMs but they eventually learn.