Sony is chasing Fortnite and Apex's billion-dollar revenues and wants to have a dozen live service games up and running in the next 3 years. Bungie will help, but don't expect all of these games to be Destiny-likes.

Sony is doubling-down on live service games and plans to release 12 live titles on the market by 2025. Earnings projections show that Sony has massive confidence these games will be successful. The company expects add-on revenues (microtransactions) to reach $24 billion by 2025, which suggests a few things.

We know that Bungie is guiding Sony's live service plans. But this level of revenue growth strongly indicates a diversified slate of games that could be outside of the types of games Bungie is known for. The sheer volume of games coupled with the significant jump to $24 billion earnings (a 7.5% CAGR growth rate) suggests that Sony's live games will deliver a broad spectrum of experiences that appeal to different demographics/age groups and types of gamers across different platforms.
In short, don't expect all of these games to be Destiny-like titles. In fact, most of them probably won't be. That's not feasible nor is it sustainable.
The majority of these games may be smaller-scale experiences that appeal to a wider base of users. Remember, live games are built on accessibility and replicability. Sony's emphasis on success shows that it's taking all types of live games into consideration and not just games like Destiny or MMORPGs like FF14.
The games could be built for younger audiences or even specific regions. Some of Sony's live games could target a specific Asian market--a region that enjoys browser-based titles (NetEase, for example, made $2.92 billion from PC browser games).

Whatever the case, Bungie will be directly involved in the live games, but it won't necessarily be developing them. Sony has said that it plans to "fully integrate Bungie expertise in all SIE processes," however Bungie is still very busy. It can assist, but co-developing 12 live games isn't reasonable. Bungie will review design/concepts, monetization & data, pre-production pipelines, and launch readiness/post-launch.
Also, not all of these live games should be dedicated console/PC titles. Sony is expanding big into mobile, and expects 20% of first-party game releases to launch on mobile by 2025. This is a considerable jump in adoption. Sony has had big success with Fate Grand Order, a live service mobile game, in Japan. The company has confirmed that Fate Grand Order developer Lasengle will help lead its push into mobile games and synergize development by lending its expertise to new teams.

Sony's confidence may also indicate more unannounced mergers and acquisitions deals specifically targeting live ops and/or mobile games.
I recently suggested that Sony needs more mobile and live operations teams to help fulfill its vision, and the mighty GAGR add-on growth does coincide with new games, but it could also indicate new highly-skilled teams and studios are joining SIE.
Let's also remember that Sony could license its IPs out to third-party studios.

Not all of its 12 live games will be developed internally. Sony simply does not have the scale for that kind of delivery (not yet, at least). Even with devs like Firesprite, Haven, Bungie, and its stable of existing first-party teams that are working on multiplayer components (Naughty Dog has Factions 2, Sucker Punch had Ghost of Tsushima Legends), this kind of delivery is extremely demanding.
For example, Sony could team up with Daybreak Games (formerly Sony Online Entertainment) to release a new live game based on one of its wholly-owned IPs. There's other live devs like, for example, Saber Interactive, who now has its own label under Embracer Group.
Whatever the case may be, Sony is all-in on live services. The company has routinely seen its partners like EA, Epic Games, and Activision make billions of dollars every year on the PlayStation Store and now it wants in on the action.
Sony is investing heavily into live games, and by 2025, the company expects that 55% of its PS5 platform investment spending will be on live games.