For a while, Spartan Locke was growing as a significant character in the Halo universe. He was one of the main playable characters alongside Master Chief in Halo 5: Guardians and even had a series dedicated to him around that timeframe. However, we all know how popular the Halo story was around that time, so does Spartan Locke appear at all in Halo Infinite?
As of this writing, Spartan Locke has no physical presence in Halo Infinite. He does not appear at all during the story in the main missions, and due to some spoiler material, we believe there is a strong chance he is no longer alive. That being said, there is no concrete evidence to prove that.
While you will not see Spartan Locke while playing Halo Infinite, there is one reference to him in the form of one of the UNSC Audio Log collectibles. In it, Dr. Halsey recommends that Locke be sent to Zeta Halo to delete Cortana until Chief declines and takes the mission himself.
We are unsure if there are any hardcore Spartan Locke fans out there. Halo 5: Guardians created a pretty significant fan outcry against various story elements and characters. It is not surprising that 343 Industries wanted to turn the attention of the franchise back on Master Chief.