I can absolutely see a future in which you get a book deal simply to then be able to earn the money you should off your own books by self-publishing once you’ve established yourself and have a reputation.
Put the legitimacy and prestige that goes along with traditional publishing can’t be understated.
With over 3 million books being published every year, it’s hard enough to stand out without publishing houses publicity machine behind you, let alone on your own as a fledgling new author.