Your analysis is correct. I recall in the mid 80's a number of Japanese PC's emerged. They all seemed to want to make a walled garden so they could sell add-ons

Your analysis is correct. I recall in the mid 80's a number of Japanese PC's emerged. They all seemed to want to make a walled garden so they could sell add-ons into it for extra $$, while, as you say 'the hills are alive' with mass made items for the emergent PC standard enabled by Microsoft's provision by sale/licence of MS-DOS while preserving their ability to sell fully compatible same-ware. There was only a small hurdle, the IBM BIOS, which IBM lawyered to death any and all copiers. Soon clean-room original BIOSes were created by a few companies and the gold rush was on. IBM had lost all hope, but sold enough to business and governments to make a good business. They tried a walled garden with OS2 and their MCA(Micro-channel architecture) bus. All US PC makers jumped on this, millions of plug in cards were made - buyers - crickets, crickets, crickets, I suspect many billions went down that rabbit hole. I recall one scrap salvager processing tens of thousands of Zenith MCA boards for gold a few years later. The Japanese finally saw the light and focussed on laptops and those had a good run, but finally they faded, IBM also made their think-pads, but eventually sold to Lenovo. Us makers - Dell, Apple and HP persist - I am not sure which are US made? https://en.wikipedia.org/wiki/List_of_laptop_brands_and_manufacturers#:~:text=The%20vast%20majority%20of%20laptops,manufacturing%20of%20laptops%20in%201988 https://en.wikipedia.org/wiki/List_of_laptop_brands_and_manu....