I don't think this is actually true. IF you go threw all the history of development economics, sure its easy to point out 'X government did X and look at that, now they are successful at X'.
However that is selection bias, government and international development agencies tried literally everything, many things 10 times, often over years and years. Often wasting resources that then didn't go into their successful part of the economy.
Quite often governments also do lead following, they do something, something else is successful, then more money flows into that and then a few years later all the bureaucrats congratulate themselves on their success.
We actually have pretty good and very clear numbers on what actually works. Basically it boils down to 'don't be a shit government' and if you manage that you will have some amount pretty good amount of growth. Avoid a few idioitic policies, implement the basic of law and business (property rights), don't punish successful people, don't be ultra protectionist.
Any country that manages that usually manages to get a fair amount of growth. It might not be growth in Steel industry but better more efficient framing, mining, tourism, labor intensive industry and stuff like that are still very helpful base to build up the basic infrastructure and business environment.
The old Post-WW2 version of 'lets not import steel, invest many billions in building our own steel industry' kind of plans actually have a terrible history of success.
But this debate has been raging for 3000 years now, in modern history mercantilism vs free market debate, then the socialism vs capitalism debate (calculation debate), then Post-WW2 development of 'Development economics' that had all these debates again. Look at India, and its strange 'Indian Socialism' based on many British ideas.
> So much like we allow children time to learn in school before we expect them to compete in the job market
Mostly what we are actually doing for most jobs is kids basically showing that they can be good little workers and have basic social skills.
For a country this would basically be, show that you respect basic property rights, don't have polices that make creating a business impossible, be reasonable accessible to global market. If you can do that, welcome to being adult, you will likely be reasonably successful.
> we should allow developing countries to employ protectionistic policies like tariffs
Allow them sure, who are we to deny them. But that doesn't mean its a good idea most of the time.