> Is teaching meaningless? I mean, why do it, when you're not going to be around when people you teach will run things.
You might be underestimating how much personal benefit a selfish materialist can wring out of teaching people things.
I, for example, love teaching people basically anything I know. To the point where I'm probably unhelpful. There have been numerous instances where there is a skill gap between me and someone else that I have closed and benefited greatly from closing. Usually this is in academic and workplace settings, but I suspect most parents would also see this dynamic. It also works socially when they return the favour and find some interesting idea for me in return at a later time.
If they don't follow my advice, that is often even better for me in the medium-long term because it suggests my advice is bad and I get an opportunity to correct my mistakes and misconceptions.
One of the most fortunate outcomes of the modern era is the more you want to maximise your own material success, the more advantage you can get from maximising the ability and resources available to those around you. I've been led to believe that a sample of most serious leadership groups will pick up an unusually high concentration of clever sociopaths - I suspect at least some of them will be excellent leaders because they figured this little factoid out.
The scenario is extremely different from someone asking me to give up driving because someone else will hypothetically benefit. As an interesting anecdata, I gave up driving because of economic and safety concerns, which are far more convincing to me personally.