Bazza, know the room.
More comments will be about your driving rather than the one you’re posting about. Jus sayin’
My turn, your following distance is much too close. You’re less than 1 second away far too often.
Your neighbor, yeah, their awareness is not very sharp.
But answer this, is it possible they were focused on how close “that truck pulling a trailer” is following?
Whichever it is, their driving is on them. Even with a tailgater ( not saying you in this case, just in general ), the driver should take action to remove the distraction. But by no means “brake check”...ever.
Increasing your following distance to 4 seconds is immensely more peaceful than you can imagine.