Not sure why the stewards gave permission for Perez to re-enter the race, the car was unfit to race, hence the retirement, then many laps later creates a risk to the remaining drivers, by driving said unfit car on the track..what should have happened is the moment Perez entered the track, a safety car was called, so that the track is safe... But no, the race director saw no problems with allowing an unsafe/damaged car on track, without any sort of notice to other drivers..
Just imagine if this track was as bad as Silverstone was, a couple seasons back, when car 44 won with 2 punctures? What if Max had needed a safety car.. Or worse, Perez broke down in a dangerous part of the track, blew an engine, fluids on the track? Max goes and bins it????
It is very clear that there are no sane rational adults running the sport... Was it legal to allow Perez on the track? Legal yes, ethical? NO, safe, No?
But will the FIA/Race Director ban this sort of insanity? Highly unlikely... It was cheating, gaming the system.. Just a plain stupid move...