On an individual basis, there's nothing wrong with "throw things on a wall and see what sticks" as long as those things are low cost and low risk. For a lot of this stuff there is no high-quality research available (and probably never will be) so you just have to do your own informal n=1 experiments to see what works for you: not truly scientific but good enough. Andrew Huberman has always been clear about which protocols are actually supported by high-quality evidence and which are just speculative.