Many thanks for reading. Two good questions. Some answers:
(1) “knowledge vs skills”: in part you restated my point. I agree, the knowledge content of a PhD is indeed always narrow, and in the vast majority of cases is useless to a future career. But the key is the skills acquired in getting that PhD. Hence I wrote about the many transferable skills that could or ought to be acquired during a PhD — and noted that much more needs to be done to support PhD candidates in obtaining the necessary skills for a job market in which academia is the minority of positions
(2) I don’t think my piece presents the bright side of a PhD. After all, it says: “that job you’re training for? You won’t get it.” Rather the purpose of the piece is two-fold: (a) deliver that message, because supervisors often do not, and that’s a failure of care; (b) give genuine hope for what else can be done.
The actual experience of doing a PhD is a different topic, and as you say the experience is often difficult in places. Mine was.