The problem is that in the case of memetic evolution the "fitness" of an idea to propagate is inversely correlated to its survival value to humans. So lots of terrible ideas have become - and continue to become - mainstream. If we think fake news is bad now imagine what it will be like in the future.
I think the main problem is that the mutation rate and transfer rate of memes is still optimized for tribal settings.
Most mutations are disadvantageous, but if you never mutate, then you can never improve, so you need some mutations to make progress.
Meme mutation rate would be influenced by the structure of the brain (i.e. how likely a neuron is to misfire or make random connections) and meme transfer rate would be influenced by instincts (i.e. how likely a person is to trust another or go along with their idea). It's possible to influence these after birth through teaching, but genetics would still play a significant role this, and genes are generally very slow to adapt.
Just a few thousand years ago (a microscopic amount of time from a genetic view), it would not be possible for humans in one part of the world to quickly spread ideas to another. If one caveman tribe develops a disadvantageous meme mutation, it's mostly limited to that tribe. That tribe with the poison meme might die out, but there are other tribes that can still exist as backups for humanity. There might be that there's a little bit of genetic meme recklessness in humans that took advantage of that for faster development (some memeticly reckless tribes got lucky and grew). But with modern, connected society, meme spreading behavior that relied on that failsafe can now threaten every human.
It will probably be several thousand years before things get better, assuming we don't drive ourselves to extinction.
The thing is, just like with genetics, we are not the arbiters of good. A meme might look bad, but if it spreads itself such that it doesn't die with it's last host, it is a good meme. Like viruses, some burn through their host population and go extinct, some cling on but are still detrimental, and some increase fitness, and now we get into the distinction between a parasite and a symbiont.
Interesting that anti-vax is a "bad" meme that actually benefits real viruses. If there were a virus that could induce susceptibility to memes that promote the virus, that would really be something.
As another poster mentioned, memes are analogous to viruses in their interaction with humans. I would hazard to guess that any survival value to humans is purely accidental, especially taking into account the time frames involved.
Certainly they do, and perhaps before the internet, a larger proportion of memes were of the useful type. For whatever reason, post-internet, memes are no longer reliant on having survival value to humans in order to propagate. Note that the converse is not true.
