I tend to side with others in the thread that the "end of general purpose computing" isn't a result of manufacturers pushing in a direction but rather following consumers. The percentage of computer scientists, programmers, and enthusiasts that consider the openness of their hardware a deal breaker grow smaller each year. For the rest of the population, they can find something that's general enough for their use cases.
Don't get me wrong, I'm all for opening hardware up and making it transparent. But until we as general consumers (not just the fine folks of Hacker News) care enough to let that sway our buying decisions, this trend is going to continue.
There will always be general hardware. It's just going to get more expensive.