The incident commonly investigated, though, is "causing a collision" (or, more seriously, "causing an avoidable accident") so, if there's no collision, there's nothing to investigate.
I'm not sure that it's a question of leniency, letting off (pardon the expression), penalisation or discrimination. Trying to be objective, an inquiry investigates and concludes innocent or guilty. Beyond that, there's the tease and hype from the TV which, naturally enough, wants to ramp up some drama and subjectively introduces 'expert opinion' on the subject, based on much less information than is available to the stewards. Put more simply, the stewards job is to objectively examine the evidence, the TV's job is to present the race in the most exciting way possible but, during the race, it's the TV's more subjective view that we receive.
