It is no secret that prolonged exposure to loud sound is highly damaging to our hearing. Listening to loud music is one of the common factors leading to degraded hearing ability and tinnitus, and is deeply unhealthy.
At the same time, such level of noise negatively impacts the quality of sound perception, which degrades the musical side of the musical performance.
In what seems to be the echoes of the so-called "loudness war", bands still stick to the idea that "the louder you blast it - the better". But it's not true. There are many other ways to energize the crowd without causing them sound damage, and I'd love to see more of those, instead of them trying to be the loudest ever.
Motorcycles are disproportionately more likely to be the source of loud, annoying engine noises, even though there are more cars than motorbikes. Loud cars are very rare, and are still quieter than any motorcycle.