>If philosophers can’t answer what makes the life meaningful
Philosophers fail here because it is beyond thinking and experience based, so one can not file a paper saying I found it - even if it is correct, it will not have any impact on others.
>how can governments maximize it?
Governments need not maximize it, they just need to create fair conditions for everyone, people inevitably will get there themselves, exactly as it's stated later:
>A revolutionary idea is that governments should leave people alone so they could pursue their well-being
>because the human mind is incapable of grasping non-linear, complex interactions
The word "mind" is not specific enough, what mentioned here is intellect. There are other dimensions to mind which are capable of much more than we can imagine.