For 1) riding backwards on the grid before the start of yesterday’s Argentine MotoGP race after his bike stalled, and not starting from pit lane as ordered:

For 2) ramming Aleix Espargaro, who was forced to quit five laps later:

And for 3) ramming nine-time world champ and fan favorite Valentino Rossi yet again, forcing him to crash:

Yes of course he should be penalized. In fact he was penalized with a ride-through for his starting grid foul-up, and he did get a 30-second penalty for knocking Rossi down again. The question is, is that enough? Has Marquez paid his debt to society?