Exactly this is happening with Apple now. Although Apple computers were fairly hackable in the past, with users being able to install Linux or Windows, that is changing. Apple is changing the hardware _and_ software to make it more difficult to do things that Apple does not approve of.
Stallman was keenly aware of this type of behaviour, and he was also aware that companies that have the potential to use this behaviour to this advantage, will often do so.
Apple wants to be in a position where they sell computers as appliances, and Apple Silicon is their step towards doing so.
By the way, I'm typing this on a Macbook pro that is no longer supported by Apple, but running Linux. I am not sure this would be possible in the world of Apple Silicon.
For infrastructure parts, it makes sense to be even permissive open source. For something in applications level, it would be nice to make money from it by charging corporations using it, while still being freely available for students and hobbyists. This could have combined best of open source and commercial software.
Stallman's belief is that everything is either good or bad, and there is nothing in between. He is write about consumerization of computing devices though.