I wasn't the one making the comparison to Boeing.
The CSIS article pointed out that the same facilities within Chinese shipyards are used for the construction of military vessels and commercial vessels, while that is not the case in Europe or the US.That makes for an easy argument to claim that foreign parties doing business with those shipyards are directly supporting China's naval construction program. That's about it.
For the most part, they are separated. For example, Jiangnan's famed fitting pool where we see destroyers were fitted has been mostly military and government vessels, along with smaller commercial ships for Chinese lines. This fitting pool is too small for many commercial ships nowadays. A shipyard in Wuhan specializes in submarines, and so is the shipyard in Bohai. Huangpu Shipyard has a divide section where one place makes the military, coast guard and government vessels, while another shipyard is purely commercial.
The main and only exception has been the carriers because they require the huge drydocks traditionally for massive commercial ships. The drydock where 003 is sitting right now, has never been used with a warship, and its only has been used with container ships. You can say, this drydock is "borrowed" for that purpose. None of China's massive drydocks were made purposely for building carriers. The commercial drydocks were borrowed for the purpose of making carriers only. But anything smaller, destroyers, frigates, and submarines, they always had specialized shipyards.
This is also true of the Dalian shipyard drydock that the Liaoning had its transformative refit from the Varyag and where Shandong was built. That drydock was borrowed and since then it has returned to making commercial ships, namely tankers. That drydock is not even close to being the biggest in Dalian, the biggest of which is 700 meters long and is partnered with Kawasaki Heavy Industries.
For a country that has at one time, as many as 3000 shipyards in its peak, the vast majority of these shipyards build only civiilan or commercial ships. I say peak because the number of China's shipyards have declined due to shipbuilding glut and because of real estate development. You make bundles more money selling older shipyards for real estate developers than operate in a loss or razor thin margins building ships year after year.
For the most part it certainly this is the case of Europe, as Fincantieri makes cruise ships and ferries, also makes FREMM and owns the Marinette shipyards that make the Freedom class LCS and the Constellation class frigates. Thyssenkrupp makes both civilian and military vessels, and they also make elevators. For CSIS to miss the obvious in their report is dope.
Daewoo, Hyundai, Samsung, Inabari and Mitsubishi all have civilian and military production. This is all common knowledge and for a long time already. Oh, and France's Naval Group? They also make high end billionaire yachts. What about Austal, whose US subsidiary make Independence class LCS and other naval vessels? In Australia they make all sorts of civilian and commercial catamarans, from high end yachts to ferries. Do they care? Does it matter? Taiwan's Evergreen shipping line has standing orders with Jiangnan Shipyard for container ships. Japan's MOL has orders with Hudong Zhonghua and COSCO has orders with Japan's Imabari.
The commercial shipping line and ship building industry for the longest time has lived in their own highly globalized world and it works for them. The epitome of globalization is in the shipping and shipbuilding business. The building of flagship commercial vessels, such as the largest of box ships, bulkers, tankers, various gas and LNG carriers, have become so specialized that European ship liners, which are still the largest in the world, source all their ships in the Far East, making multiple orders in China, Japan and S. Korea. European shipbuilders have concentrated in cruise ships, ferries and yachts. Japan has already gotten into the cruise ship business, namely for Princess Cruise lines, and you should know their names because of the pandemic. China is increasingly doing cruise ships, although not as big or high end as the Europeans. Their first high end cruise ship is a replica of the Titanic with a Chinese shipyard that happens to be in partnership with an
Australian billionaire and company.