Could he just be pandering to his hosts? The concentration of talent and a whole ecosystem that supports entrepreneurs is a significant advantage. It will take time for any other region to amass the same advantages.
That's inherent to the process of all creation and business starting. 90% of everything is garbage. That's a case where there's nothing unique about Silicon Valley. I'm sure you're at least vaguely aware of the very high failure rate of all new businesses within just a five year span.
Or see: last 200 years of industrial history. There were hundreds of automakers just in Detroit in the US, experimenting with just about everything they could. Most of it was garbage. It's a required part of the process of experimentation. If someone stands up and proclaims that aspect is stupid and a waste and they know better (they'd never make such mistakes, they'd never need to perform such wasteful experimentation), well, at least then you know who you're dealing with.
Silicon Valley's 10% is better than the 10% anyone else produces. It also does it at a higher volume simultaneously. That's why it's Silicon Valley and nobody has managed to match it in the last 50 years.
SV is good at what it does, it's the best at what it does, but that's orthogonal to building a great company. We believe it's necessary because that's how it has been done.