Those days are coming to a taper quicker than people may think. There's a LOT of economic and geopolitical pressure pushing against China right now.
First is the logistics issue caused by the increase in containerized shipping costs. It used to cost about $2500 to ship a full sized container from China to Long Beach, CA. Now it costs $25,000.
Then, good luck unloading the container in North America with any sort of expediency. Container ships are lined up waiting to port on both coasts right now. Part of the issue is logistical in North America with a shortage of truck drivers to move the freight away from the docs.
Then, the issues surrounding mainland China and Taiwan are starting to heat up again. If the mainland decides to attempt to retake Taiwan, the economic consequences will be world wide, but the mainland will feel the brunt of it. There's all ready sabre rattling on both sides of this issue (This is a business/economic observation, and not a political point. I'm not concerned with the politics of the situation, just the impact on supply chains and manufacturing).
On top of that is the energy crisis in Mainland China.
You can have all the inexpensive labor you want, but if you can't run factories because there's no power, and you can't ship the products you do make to customers, it's becomes really difficult to make money at all. Even if you can ship, the cost has increased to a level that tips the balance of profit and ability to deliver to a negative. It may cost more to manufacture someplace else, but if you can guarantee production, some profit is better than none or the inability to deliver consistently.
A lot of companies and stockholders made a great deal of money on the Chinese gold rush of the past 20+ years, but every party ends sooner or later. It would appear that circumstances are aligning to bring that era to what will probably be a slow decline. Not an end, but the gold rush days are probably over now.