Whilst I do believe some of what Mr.Ceder says is rooted deeply in facts, the underlying idea still is driven in my opinion a lot by idealism. Whilst in theroy this might work, and we could theoretically find a lot of these materials with desireable properties, most materials are defined by their defects and their imperfactions rather than their structure on its own.
For this we can look for example to diamont, where defects actually give us the color we expect from the diamant, rather than what is the ‘true’ color of the material.

The bottomline is that practically speaking, we cannot make defect-free materials that easily and thus a lot more material compounds exist outside of the ‘perfect’ ones.