To grow food in a truly sustainable way, we need to really understand the laws of biology at a macro and micro level (soil biology, water cycle, carbon cycle, etc...). Our scientific systems are not working efficiently towards that necessary understanding. 2/3 of life forms by mass in soil are microbes and we know nothing about 99% of them. We just know that soil biodiversity and food production/quality are highly correlated. If we don't work on this correctly, in the end, we will end up in a dead end and join the 99% of species that disappeared since life exists on earth in the long term. Odds are against us but I'm working with scientists and professionals that are having incredible results.

maybe he means it's too complex for science to rediscover. maybe rediscovering/using ancient wisdom regarding this domain is better. but this is just intuition