I wonder, does Mr Stewart have the impartiality to make such a comment?
I'll bet the under on that.
Article reads like the point of view of a very annoyed traveler, whose flight was delayed 5+ hours, whose plane had to divert for some sort of malfunction (maybe the upset cabin crew had family waiting for them, had an anniversary to celebrate, etc?) and who wasn't impressed by the charm of Germany's flagship airline and its customer relations department.
My guess from the flight deck; it was a frustrating flight (see the Mx delays and pax having to be off=loaded), then having smoke and fumes in the cockpit/cabin (over the big Pond) may have been doubly frustrating for them but they ... DID THE RIGHT THING ... and put the bird on the ground to ensure that their aircraft and their passengers were OK.
I can imagine the Captain's patience was tried a bit by the "revolt in the business class" of people demanding that he debrief them. I think they don't realize that he'd doubtless had ample comms with LH home base and had to debrief them, eh?
A crap event for everyone, except that all souls arrived, eventually, from Mexico City to Frankfurt.