I would have to argue that learning a good basic fish-in cycling process is just as easy at learning how to fishless cycle. I think it's important to further define fish-in cycle in this context as a controlled method, rather than a by-product of a new fishkeeper spending venture.
No, you can't take a brand new 10 gallon and put 10 fish in it. You also can't just dump a bottle of ammonia in it either. So following a basic guideline goes a long way for both methods.
Both methods utilize regular testing, so there's not much of a difference there.
So I guess it comes down to their ability to follow directions.
If you are stocking properly (i.e. slowly and slightly) then the chances of a fish being stressed due to new tank syndrome are minimized greatly, and any ammonia that is being created will be registered on a test well before it has an impact on the fish in the tank.
And everyone learns how to do a water change pretty quickly, it's not rocket surgery, and I don't see how this makes the case for fishless cycling. If someone isn't capable of doing a water change they probably shouldn't be caring for a fish tank.
I do agree that fishless cycling teaches patience, usually to an entire family since they all get to stare at an empty tank. Learning patience is good, I just don't see why it is necessarily an applicable chore that every new fishkeeper should be going through. Fish-in cycling requires a lot of patience as well as control, if you consider that a person has to make a conscious decision of what, how much they stock, and when.
You make a good point that the fishless process gives a person time to do research and learn more about fishkeeping, but not everyone needs a 3-4 week period to do that. And some people do their research long before they get their tank, or they let their tank sit empty till they get a good gameplan.
There are a A LOT of people who walk out of a pet store with a bag of fish under one arm and a tank under the other. The solution for fishless cyclers is to tell them to return all their fish to the store, which most people shrug off. These scenarios are often used as an example that the fishless cyclers point at when they talk about crazy water changes, sick fish, and stress all around.
My solution is to teach them about the nitrogen cycle so they get an understanding of why things are happening in the tank, and the way to fix them.