To prevent chaos when a car doesn’t budge at the start of a race, please make all cars automatically ghosted/intangible by default at the start of all public multiplayer races until throttle input is detected from their drivers/players.
There’s at least a 90-second gap/intermission (including loading screens) between the end of practice/qualifying & the start of a race during which players cannot quit/exit the lobby (without dashboarding or powering off to force a total game shutdown)…
…If someone steps away from the game during that intermission, their unattended car remains on the grid as a roadblock for others who are trying to get a good start off the line.