New forms of government, larger and more complicated corporations, public schooling, labor unions, global shipping routes, universities, remote work, wikipedia, internet forums, open-source software development, stock markets, etc etc.
None of these required a genetic change in the individuals involved, just a "memetic" change in the way the individuals acted, communicated, and thought.
horizontal transfer via memetics is not guaranteed to be a productive or stabilizing force in the long term, it could be convincingly argued many of our nastiest problems today derive from immaturity in handling novel forms of information flow and hybrid agency enabled by modern social and physical technology
the task, imo, is to remove memetic agency from the driver's seat and put ourselves back in it, or if we want a chauffeur at least to make sure it's taking us into a viable future
None of these required a genetic change in the individuals involved, just a "memetic" change in the way the individuals acted, communicated, and thought.