I think it's important to take a hard line here. Otherwise in the future we are not going to own any of the devices we buy.
We're almost there with our phones. At least on Android one can install 3rd party apps.
So I think RMS is spot on.
I like to own my device. Write, compile, and install software of my choosing on it, without some company getting into the way of that.
Companies want to control and monetize every possible use of our devices. We can't let that happen unchecked.
The again, in reality I take a less idealistic stance:
- I accept that the BIOS, drivers for the graphics card and the wifi chip are - for the time being - proprietary.
- For everything else I see absolutely no reason why I should use any closed source software.
- My OS is open source, all applications are open source, all games I (occasionally) play are open source.