This kind of thing isn't totally out of the question. The mandarins famously shut down China's budding sea voyages because they were run by a eunuch, and the mandarins and the eunuchs were opposed factions. https://en.wikipedia.org/wiki/Zheng_He

But there was never a Chinese ideological opposition to peasants becoming rich; the theory advanced by AnimalMuppet makes no sense.

The Wikipedia article you referenced has much interesting information, including "China ... embarked upon a massive and expensive expansion of the Great Wall of China. In this environment, funding for naval expeditions simply did not happen"; and Zheng He's part in spreading Chinese influence throughout South-East Asia.

Or, they shut down those voyages because they were economically absurd.

> That does not sound like a good argument at all. Metal for vast majority of human history gave you massive edge in weapon technology. Some Mandarin just shut something like that down? Seems super unlikely

The assumption here is that every thing works in a clear way so you can see the military or whatever advantages of a particular phenomenon. Now I don't know if AnimalMuppet is literally correct that the bureaucracy simply shut down the steel industry -- but if it happened it would be because all that cheep steel was not being used for obvious things, like the imperial army, but for other unexpected uses. Maybe arms and armour still had to be made the old fashioned way anyhow, so there was no immediate military advantage.

More likely, things were subtler. Things innovations can strangled long before their importance is clear. Imperial China had a vibrant merchant class, but it isn't the kind of place that is likely to tolerate the "disruptive innovation" which fuelled Britain's Industrial Revolution -- where a bunch of upstarts come and do things with unexpected things. Even modern China (or for that matter the modern United States) struggles with it.

Perhaps that was Wootz steel from southern India?

https://en.wikipedia.org/wiki/Wootz_steel