Two things: I got an Powermac G5 @ 2.7 GHz and the only time it feels slow is when I surf at some heavy web pages (which usually feels sluggish (but not as sluggish) on my quad core pc too), but considering that Amiga was in the internet dark ages just a few years ago I can't complain. Oh, and 1080p MKV movies don't fare too well either but I can live with that. I don't use NG Amigas because of it's power.
Second, please stop complaining about the pricy hardware and that "we must" switch to this or that architecture. The reason we have pricy hardware is because an architectural shift is a huge undertaking with no garuantee of success. So someone actually opened up their wallets to make this hardware so we would have something to play with at all.
As for Amiga becoming mainstream again ... Yeah right. That ship sailed when Escom went belly up in 1996. After that Windows 95, Linux and later OSX came and became the laymens choice of OS. That will not change. We might love AmigaOS, but most people are happy having an app launcher.
Sit back, relax and have fun with what we do have. It's not bad, really!