This was written in 2002, I can’t fault Joel for not having perfect foresight.
But if I squint I can see the strategy. First you got to get rid of the industries dependency on Microsoft, if you can get developers comfortable with Java, Microsoft Windows was not going to focus on making Windows Servers the best place to run Java.
Java could have very well been the “nose of the camel in the tent”.
Javascript was definitely an attempt to commoditize “where you run applications” to get more people running apps in the browser.
I think the motivation is backwards. Many employees and even executives are highly motivated by moral arguments. They want to do good in the world, and get paid for it. But to do so they have to justify it with a business case.
IOW, the moral argument comes first, the business case follows.