I've read the Qing really turned China back. The Ming were building ports and fleets, but these seemed threatening to the Qing and they scotched it all and turned inwards.
China had plenty of competition, but most of them were nomads who didn't even invest that much into agriculture, let alone industries. The exception might have been the Song dynasty, where it's main rivals, the Khitans, Jurchens, and Tanguts all eventually adopted the permanent settlement life style and had similar technological abilities. That was perhaps why science flourished during the Song dynasty, especially firearms.
Since then most Chinese empires dominated the region pretty much unopposed...
Although, if conflict, competition and cooperation are the keys to innovation and inventions, places like India should see more technological innovations. India had been fractured into many little kingdoms throughout most of its history much like Europe. Maybe it was the Muslims, Mughals and the Europeans that pulled them back. Before that Indian sailors were spreading Indian culture to South East Asia. After the Muslim conquest, the same routes were taken over by Muslim sailors.
By the way, the Ming dynasty was at time against maritime activities as well. In fact, since the first Ming emperor, Emperor Hongwu, a.k.a. Zhu Yuan-zhang, Ming banned ocean travel by Chinese private citizens for 200 years. That's 75% of the Ming's entire history. People like Zheng He operated on official capacities and sailed the seas were rare. Ming dynasty forbade most civilian coastal activities because they fear people would collude with foreign privateers (Japanese and European pirates).
In both alleged plans to overthrow Emperor Hongwu, prosecutors implicated the suspects with "plotting with Japanese pirates." These two cases resulted in mass execution of the suspects' associates and families. A total of 45,000 people were executed with the "Japanese pirates" excuse. Whether those are trumped up charges or not, it signifies that the Japanese pirates was a serious issue to Emperor Hongwu.
In the Ming Code of Law, Emperor Hongwu banned building ships with 3 masts or above. People not on official capacities are forbidden to carry trade goods or weapons to foreign counties, or to pirates. Punishment for disobeying this law was death. The perpetrator’s head would be hang for the public to see, families would serve as slaves or border patrols in remote places for life. Same goes with those who sell ships to foreigners.
Emperor Hongwu also closed down Maritime trade offices (市舶司) in Quanzhou (Fujian), Mingzhou (Ningpo today), and Guangzhou (Guangdong). Those offices had been in place since the Tang dynasty.
All these measures effectively put Chinese maritime development to a halt. The Qing merely readopted these policies.