That's how ya see it huh?
You need to go to a few more drag races.
If it were like you say, Nobody would make it to the finals.

Most times, even when they blow up they do not wreck.
Most times the engine can be rebuilt between rounds.
and this has strayed way off topic.
I still have friends in drag racing and I will see what I can find out about the graphite.
People who know nothing about drag racing should avoid pontificating on that they know nothing about.
BTW
Yes they have a sheild for the diff, but I have never needed it going back to '65 and haven't seen a modern T/F or F/C rear end blow in a dangerous manner anytime in recent memory.
I mean I'm sure there is a case somewhere but it's waaaaaaay uncommon.
I'd bet a Competition class dragster hits the gear harder. Let alone a Pro Stock car.