Your Halo Infinite rank is probably going to be lowered by a full tier
In a new Halo Waypoint post, 343 community manager, John Junyszek, announced that Halo Infinite competitive players are going to see a mid-season rank reset. The post also told players to expect to find themselves a full tier lower in rank than before due to tweaks to the game's skill assessment system.
According to Junyszek, 343 has determined that Infinite's "Competitive Skill Ranking" system has been "overly generous" in Infinite's first few months post-launch. This has led to an uneven distribution of players across Infinite's competitive tiers, and 343 hopes that the new changes to CSR it is rolling out will more accurately reflect players' skill levels.
Additionally, 343 will be resetting all players' competitive ranks, requiring them to play through their placement matches again. 343's assessment is that most players were set a full tier above where they belonged, and as such "...most players should expect to be placed a full tier lower (Diamond players will find themselves in Platinum, Platinum players will find themselves in Gold, etc.)"
One caveat is that players who made it to Onyx (the highest rank) will likely be placed in Diamond 5, right on the cusp of making it back into Onyx, as opposed to the previous placement cap of Diamond 1. As Onyx players have to have climbed the ranks to reach that spot, 343 expects their rank to have more accurately reflected their skill level even in the previous system.
Junyszek also mentioned that 343 reserves the right to make similar changes in the future stating "That said, this isn't the end of our updates to ranked, it's only the beginning. There is still more to go after, and we'll continue to make updates based on your feedback and live game data." The discussed round of adjustments will go live on February 22.
This all seems like the necessary work of maintaining healthy competitive matchmaking, especially given the game's relatively recent launch. Still, I recall a past self who would have been devastated if his Overwatch rank had been lowered a full tier, even if such changes show how malleable and impermanent competitive ranks are in the first place.