The slogan is true and useful to know. If I don't know anything about VScode and I land on the page and I see that it's built on open source I would find that interesting. If I was a reasonable person the first thing I would do is then read further and find out more about the project. I would find that most of the code is released under MIT and that the release build from microsoft has other proprietary modules attached. I could then delve deeper and make a rational decision as to whether this tool is suitable for my project or business.

The first thing I would NOT do is get on hacker news and bitch about how the project is being deceptive and evil. That is just lazy and entitled thinking.