The choice [of a Broadcom SoC] by the RPi-team was utterly stupid and can only be attributed to incompetence.
Well, Eben Upton's job working for Broadcom was probably a factor there... Personally, I'd trace the idea back before he had that job - I recall a discussion about the Gameboy Advance developer kit in the summer of 2002, and the lack of affordable programmable devices at the time. I suspect he'd have had a real struggle getting anywhere close to the Pi's target price without getting discounted access to the Broadcom SoC he used, though. I haven't spoken to him recently, but my impression was that far from "RPi Foundation pressed Broadcom to stop selling BCM2835 to competing projects" as claimed, it was more "Eben twisted arms and got Broadcom to give RPF a special cut-price deal so they could afford it".
If anyone were to bring out a rival device from a "significantly superior" competitor, I'd be delighted to see it - and I suspect most if not all of the RPF people would too, since it wasn't about making money by selling lots of systems. (Of course, Broadcom didn't buy up the remains of ARM's parent company for nothing, so I'd be surprised to see something much better from a rival!) I was happy to see the Pi being ARM based, as a fan of ARM as far back as the ARM2 I first programmed, but I'm also happy to see rivals like the MIPS32 one mentioned recently: I like ARM, but I also like having a choice of platform, both hardware and software!