Can't progress Elbrus quest without earning psycho intel. Game too dumb to register 'earning' if your inventory of it is full. Have to delete the entire brick of it to 'earn' more, then can't open chest to further progress quest without getting more psycho intel. Bungo, couldn't you have made the logic detect amount acquired (e.g. from a strike) some way other than simply based on a delta in the inventory amount? Sheesh, stupid logic. Or yet another pathetic negative QOL thing meant to extend grind. Dumb either way.
I wanna say troll, but for the chance you may be serious:
You don't have to trash the intel, just run PysOps and pop the chest. Run more than one pysops as you need to run 6 total in a week IIRC to get those powerful rewards. Burn through all your Intel so you have room rather than through it away. That's on you.