No they aren't, but it makes them feel less shitty about the behavior.

Oh I agree, motorcycle riding is a very risky thing to do. There's effectively no protection. It's not a good idea, even without the context of other drivers. Worse, if you have an accident then the motorcycle becomes a 500-lb hazard .

I think it's completely understandable that a rider wants to be loud though, especially in the present with so many drivers looking at their phones instead of watching the road.

Motorcycles are fun as hell, but safety has nothing to do with loudness and everything to do with hyper situational awareness and anticipating problems. The fatality curve peaks squarely in the Dunning-Kruger zone. New riders make mistakes but usually resulting in no or lesser injuries because they're scared and careful. It's when people get (over) confident at a year or so that the real problems come, usually resulting in a really bad scare or death or major injury. Those that (can and do) continue become super aware of their surroundings and are mostly the safest drivers out there, and the death and accident rate goes way down.

Truthfully driving societies would be way better off if people had to start on motorbikes (or ebikes) before starting to drive around 2 tons of death, the awareness stays with you. That said, fuck cars.

None of any of that has anything to do with noise, cars are sound isolated against their own noise FFS. In aggregate cars make much more noise than motorbikes anyway, sheer numbers, it's just that you notice the dickhead with the loud pipes more (when you're not in a sound isolating car).

you can absolutely hear a loud bike approaching your blind spot, which is kind of the important time to be noticing them

even I can hear them with my half deafness and shitty loud car that you have to yell in to have a conversation on the highway

Public transit? Do I hear public transit?