DLC for physical games, starting with Horse Armor era, really didn't make sense. I'm talking regular old DLC, not expansions. Expansions have been fine for a long time. DLC for digital platform games ended up being a no brainer.
In reality, DLC is a big buzz word for console games because console gamers hadn't realised they were just playing low-end computer games. So of course, then console games started using the traditional add-on method that had been previously only used for computer games. It is even more obvious as now we are seeing full games released under the old "shareware" type model (without the sharing part) where they do not have the full game at launch and have to buy the rest of the levels or episodes later on.
Welcome to the 90s!