It sure seems like the news editorial desk is dead, but genre fiction has had this issue since forever - Dickens for example made most of his income from serial fiction and it paid to be expansive. Fantasy fiction seems to have had the phenomenon of authors starting out writing a decently tight first book only to publish a series of ever-expanding doorstoppers for a while, at least since the 80’s. Maybe successful authors have bigger egos and/or more leverage and that results in less of a tendency to self-edit or accept editorial advice.