Ah, Paul, now you ARE showing your age
It appears to me that the tuning mantra for today's younger enthusiasts is more noise the better even if it means, usually. less performance
You only have to look at the tail pipe sizes to realise that most of then haven't the slightest idea what they are doing! If they are only interested in 'style over function' then I have no problem with that, but they shouldn't confuse style with performance.
For example, my project will be using, probably, a 75mm ID exhaust pipe with a 90mm tailpipe. This will be sufficient for the 500 odd horses galloping out of the back. The final sizes will be determined on the dyno.
What were we talking about? Oh, yeah, screamer pipes. Seems to me that their only functions are as a fashion accessory and blue meanie magnet
But, then I am 55 so what do I know? BUT, once a boy racer, always a boy racer (at heart).