He calls Linus out for being a toxic element in the open source (or at least Linux) ecosystem. This is quite probably true.

Trying to look at it from the other side, though, I wonder if Linus got to be the way he is because it's how he copes with the toxic effluvia he has to deal with on a regular basis. Surely Torvalds has to deal with even more of this than Poettering does. If these things were directed at me on a regular basis, I can't claim with confidence that my moral fortitude would be up to the task of remaining easy to work with either.