Koala I do indeed let my children be children - my 6 year old wants to be left home alone for 15 minutes. I think it is the right thing to do - everything gradually and at the pace the child is happy with, not all in one go when it is a novelty at 10 or 11...
The easy way is not always the best way, and learning to use a phone and what to do in a fire and how to get help is all fun at 6.
I have also made sure he knows how to let himself into the house with a key, by letting him do this every time we arrive home together even though it takes longer than doing it myself.
Just as I encouraged the kids to dress themselves and spread butter on their toast at 2-3 even though obviously doing it myself would be faster and easier.
Kids like learning new things, and I think it is pretty much 80% of my job description to be doing all this, not to treat them as tiny helpless useless vulnerable creatures who can't be allowed any freedom or to do anything themselves until some magical age at which they are thrown in the deep end.
In practice most people are "elaborately preparing" their children for independence pretty much constantly without thinking about it, that's what bringing children up is, beyond the absolute basics of love, food, clothing, shelter...