This just occured to me:
Could it be possible that the earning system in Halo Infinite is cR based instead of XP?
In Halo Reach, all armor related items were unlocked by purchasing them with credits. I’m thinking maybe a good portion of the base armory in Infinite are obtained by credits while the battle pass items introduced each season are obtained by XP. Meaning only completing challenges to progress unless you spend your currency on skipping tiers instead of unlocking armor already available in the base game.
A little convoluted, I know, however this could be the route that they are going. Could explain why we weren’t earning anything during the technical preview after each match since you could buy most of the tiers with the credits they afforded to us.