I would warmly recommend the last chapter(s) of 'The Selfish Gene'. Now an aged book but still largely up to date. In those last chapter(s) Dawkins invented the word meme as analogy to gene: a meme is a self-replicating piece of information. Like genes that are successful (in the environment they are in) propagate so do memes that are successful. Religion is the ultimate meme complex, it is a set of ideas that lives 'on top of' us and as long as it doesn't kill its host it may spread further.
In that sense, while I would guess at minimum religion can't kill its host, it does from this logic not necessarily benefit the host. An aggressively missionising or crusading religion might outcompete one that is peaceful and better for its host. And even a peaceful variant (see original Buddhism or zen Buddhism) might evolve into an aggressive, exclusive and murderous ones (see Buddhist monks in Myanmar firing up and demanding the genocide of the mostly muslim rohingya ethnic group).
I don't think you have correct examples of memes not benefiting their hosts. Those are examples of them not benefiting other people who aren't the hosts. A better example would be something like martyrdom. A religion that's perfect for its host might turn out to be one that exterminates or enslaves all non-hosts - if it could somehow achieve that without sacrificing its own hosts.
The articles premise that Americans acted kinder for a little while after doing some Buddhist meditation.... Completely ignoring the fact that Buddhism has extremists just like other religions...
The people didn't act kinder because of Buddhism. The experimental setup primed them to act in a certain way.
In that sense, while I would guess at minimum religion can't kill its host, it does from this logic not necessarily benefit the host. An aggressively missionising or crusading religion might outcompete one that is peaceful and better for its host. And even a peaceful variant (see original Buddhism or zen Buddhism) might evolve into an aggressive, exclusive and murderous ones (see Buddhist monks in Myanmar firing up and demanding the genocide of the mostly muslim rohingya ethnic group).