While you could play Doom and SFII and more games online using Xband on SNES. Dreamcast launched in 1998-1999 with a built-in modem and a big marketing point for SEGA was online play. DC had the first console MMO. Sports games early on showed online competitive play. While SEGA planned a Saturn variant with a modem built in. Only prototypes exist. Still had to use Xband if you wanted to go online so in a game like Saturn Bomberman you could go online. Battle Royal 90s style.
Dreamcast offered DLC for console games (tho N64 DD did as well) for Sonic Adventure. Skies of Arcadia and more. If you think Ubisoft making physical games useless is a new idea. PoD on DC is almost worthless now without servers. Online has been both a gift and a curse. A gift in the wonderful things it can benefit gaming and a curse for how publishers now abuse it like Gaas. Ubisoft requiring online for SP games. Epic Launchers on console. Same with Bethesda. MTX.
Where online flourishes is Co-Op which is great. Competitive play. Tho another feature I like with online. PS5 offers this. Last year I was struggling in a couple parts of a game. I handed my controller to a friend across the country and I watched him play my game. That was cool. When used right online is one of the best things to evolve this centry. Sadly it's mostly been used for greedy bullshit.