The evolution in paragraphs is a reflection of the medium. Long, verbose paragraphs are harder to read on-screen, which is what drives shorter, snappier paragraph adoption. This isn't new - it's standard practice for companies doing more on-screen stuff, and it has been well-known in the industry for many years now.
The content shouldn't change just because the presentation changes: any complaints about slipping journalistic standards will have to stand on their own, and can't be rolled up along with paragraph-length as a catch-all "the Beeb isn't what it used to be..!" complaint.