Good thing Infinite didn't end on a cliffhanger! /si mean, if people are still playing it they'll keep putting out a season pass from time to time. i'm sure the RoI is okay when it's just a guy putting like 50 hours of effort into making a few guns a slightly different color.... i'm being a bit of a sucker here but that's effectively what season passes are for any GaaS featuring a battle pass.
The campaign really sucked at times but it teased a lot of potential. I really hoped for once 343i would be able to just make a sequel/expansion instead of another reboot.
No clue what they'll do with multiplayer. It finally got its big update and is as popular as The Master Chief Collection on Steam.
they'll make sure the servers are still running. make a new map or two. maybe a new mode even. however, i just don't expect any big investments if the campaign team was killed. they'll just keep the lights on and the existing fanbase from becoming angry.