> What specific part of my comment gave you the impression that he’s replaceable?

I think but obviously can't confirm it might have been this bit:

> ... at least Stallman comes to mind as an example of someone who was able to change the course of history *without much personal power, instead he crafted ideas that had power.*

To me this might be construed as Stallman could be replaced by anyone, since he had little personal power and only crafted ideas; anyone could craft ideas.

I might be wrong though but that would be my guess