The article doesn't really answer the "why" part. Basically, it sounds like there were a lot of small things, mostly changing culinary influences. Of course, that doesn't answer the question of why they lost their taste for cilantro but not other herbs. Don't get me wrong, I liked learning the history, but it's a bad headline.
I think it gives the answer but very briefly - "It clashed with expensive foreign spices". Essentially the Italian cuisine that formed wasn't really compatible with coriander.
I like coriander but my general sense is there aren't any Italian dishes I'd want to add it to whereas it's perfect with many Mexican, Indian and Chinese dishes I know of.
