Interestingly, one of my old colleagues has research that examines exercise / sport practice in humans as an alternative to the WM training approach. (You two might get along :).

https://scholar.google.com/citations?user=_0GhDagAAAAJ

Can you share some more recommendations or advice on how one can increase neuroplasticity/neurogenesis?

Aside from the diet/exercise/socialization/meditation, what should people be aware of?

Are there some effective supplements/nootropics, or some promising research to look into?

I left academia about five years ago, and don't want to create the impression that I'm some brilliant academic researcher (I spent three years doing rat/staining/counting work in a lab and wrote an honors thesis on the topic). I try to keep up on current research when I can though, the work pretty much consumed my life and I kind of miss it sometimes.

Regular aerobic exercise (stuff that elevates your heart rate) is still the best thing we know of. It's good for upregulation of neurogenesis and BDNF.

There are dozens of papers out there showing that a certain treatment/activity/drug increases neurogenesis. It's funny, I was talking about neuroscience to a lyft driver a way back who was curious about neurogenesis/neuroplasticity, and I told him that exercise is your best bet, but we also had some good results treating our brain-damaged rats with an acetylcholinesterase inhibitor. He shrugged off the exercise bit but of course asked me to spell out ACh inhibitor for him (which I really wouldn't recommend any random person off the street taking).

I experimented for a bit with nootropics after I graduated. Gwern's posts are really interesting if you haven't read him (https://www.gwern.net/Nootropics). A number of people have found success with a basic choline and -racetam stack. As much as tech blogs love blogging about how we're all hooked on nootropics in the valley, it's unlikely that taking some pills in the morning is going to dramatically change your life (though it might nudge it in the right direction). As one of the other replies said, lifestyle changes are still the most effective approach.

Cognitive improvement won't be found in drugs or supplements. The answer is in lifestyle change and recognizing the body and mind as one system.

As far as your question about taking drugs/supplements to increase cognitive function, I can say with certainty any positive effect in the short term will eventually fall to long term dependencies and addictions which will, in turn actually decrease your resting cognitive function.