No, Halo Infinite has not been delayed again, 343 Industries say
We've been around this ring before
Hold your warthogs folks, 343 Industries are setting a few things straight about Halo Infinite delays. It is true that 343 announced earlier this month that they would delay Halo Infinite from late 2020 to sometime in 2021. That bit was officially announced. What aren't real, they say, are the subsequent rumors that Infinite could be delayed even further into the following year. We should still be expecting it in 2021, all clear?
343 Industries stepped up to clear the air after rumors started flying about calling their new 2021 plans into question. A poster on ResetEra, who might be someone in the know on Infinite, claimed that the studio is considering pushing the release back again into 2022. They also claim that an Xbox One version of the game is being called into question in favor of only supporting the Xbox Series X.
Halo esports player "Snip3down" caught wind of the rumors as well, which seems to be part of what prompted 343 Industries to squash them. 343 community manager John Junyszek says that "there are no plans to change our 2021 release or the devices and platforms we'll be supporting."
Earlier rumors, which turned out to be more credible, suggested that Halo Infinite could cleave off its multiplayer modes and release them first while only delaying the campaign. 343 did consider that option, Xbox head Phil Spencer confirmed, but decided against it. "It just didn’t feel, to all of us, like the Halo release that we would want," he said.
As a recap then, Halo Infinite's multiplayer and singleplayer will launch together (though the multiplayer will be free-to-play), they still plan to release an Xbox One version, and Halo Infinite has been delayed to 2021 but no later. Not as of now, anyway.