It's been like this for quite a long time, but now it's really starting to bother me. Back in Destiny 1 and such, primary weaponry were still very good DPS tools on bosses. The damage wasn't too low in comparison to the other options you had, and they did a pretty good job for things like damage phases on raid bosses and such. Nowadays, the issue, or issues are clear as day with how weapon types are balanced in terms of damage in PvE activities. Either: 1)The other two damage types are doing too much damage to give primaries a chance to do anything worthwhile or 2)The bosses have too much resilience to primary ammunition like how a lot of supers have a ton of resistance in crucible. The second one sort of stems into a bigger issue of Destiny 2 not allowing for that much variety in how to combat certain opponents, but I'll leave that discussion for another day after I go get killed by a spectral blades or a sentinel some more. But anyways, and in conclusion: Primaries just need to become decent enough to use against bosses when you have no other ammo available. I don't like having a weapon slot that's essentially only there to drop more of the other ammo types from ad clearing and do practically nothing else.