For future sports rights contracts that commence in 2030 or later, they'll ALL be centered on streaming, with any linear rights simply going to whichever channels that still exist that are tied to the streamers (e.g. Paramount+ and CBS). But a lot of sports will be carried exclusively on streaming, because I don't see Netflix, Amazon or Apple ever launching traditional linear channels.
As for ESPN, the *original* basic cable network, I have a hard time seeing how it survives long-term, even as a streaming service. When Disney finally takes the entirety of ESPN to market as a standalone direct-to-consumer streaming service (maybe around '24), I think they'll have to split it up so as not to have one big thing with sticker-shock pricing. I could see them do an "ESPN Pro" app and an "ESPN College" app. Each might cost $15 on a monthly basis (with unskippable targeted ads in both live games and on-demand replays), but with some amount of discount for bundling the two and/or pre-paying on an annual basis.
But longer term, I think all the major pro sports leagues (except maybe the NFL) -- MLB, NBA, NHL, MLS -- as well as the NCAA (or at least its two power conferences, the SEC and Big 10) end up either doing their own direct-to-consumer thing or just partnering up with an exclusive distributor to handle it, as the MLS is doing on the streaming side with Apple. "Here's the price for a single team season pass (whether in or out of market), here's the price for an all-team season pass, here's the price to buy access to X individual games of your choice." But all those sports will want to also allow broader audiences to sample a certain number of their live games, either in free apps (e.g. YouTube, Pluto TV, etc.) or in very popular mainstream entertainment subscription apps (e.g. Prime Video, Netflix, Disney+). Gotta keep hooking new young fans or the sport will die.