Graves build up his general system from numerous interviews, inspired by Maslow's pyramid of needs. The progression of values fairly reflects available resources (individually or collectively). The odd-numbered values transpire to be ego-centric (so to speak), while even-number numbered are "society" centric.

The liberals (and socialists) fall neatly into the value level #6: humanistic values, human rights; opposing extreme inequality and hierarchy; providing satisfactory living standards to everyone; supporting sexual choice, etc. The conservatives are represented by a mixed bag in this system: #4 (traditional society values, religion); #3 (authoritarian leadership of various sorts); #5 (entrepreneurship, opportunistic autonomy). The reason that conservatism encompasses a few different value systems is that those systems co-existed for centuries already. Besides, the meta-level #7 (awareness that values are not absolute, and using that for personal benefit) generally favors conservativism as well.

Within this paradigm, the general liberal direction in the last century is well explained by unprecedented abundance of resources. Extrapolation to a bright liberal future is then reasonable only assuming the same abundance of resource further down. But if resources become tight instead, prevalence of the value level #6 is in deep trouble. Firstly, it will badly become a punching bag for the conservatives and #7, as they are more eagerly perceptive of resource limitations. Secondly, it will be tougher to sustain or buy #6 personally, with the personal share of resources and benefits becoming unsatisfactory. Liberals will prevail in the biggest cities pretty long, as this is where resources and services are concentrated. But the liberals (generally) find themselves already pretty low in the financial food chain and social influence. Habitually, they profess their values passively and have intrinsic leadership issues. No wonder that they were led by #7 wolves in the last two decades to wholesome irrelevance. The progress in LGBT rights only masks the lost ground on social-economic issues.

Genetics is surely not a dominant factor in the Graves value system. Rather explicitly, it is postulated that Graves' values "progress" pretty inevitably with a larger cake of resources. In particular, #6 is dependent on the level of education, and appearance of having enough to everyone. Genetics might play a role in flexibility, readiness to embrace or avoid particular value systems. For example, (non)stickiness to authority dynamics might be a genetic determinant for #6 acceptance.

What I notice is that there are several trends heralding a depression of #6 values. The brief rise and fall of #6 might be a recurrent story of great civilizations.