That includes MSQ and related trials, Job quests and related trials....

I understand the game wasn't designed to be this way, but still... I feel my friends and company members can't join with me on like half of the game

Since it takes a while to complete Main Scenario Quests (like months!) and unlock various content, I feel it negatively impacts your best friends from being able to participate in a lot of stuff. We all have separate lives on the outside, so it is quite unreasonable to expect that myself and my best friends will be able to do the same dungeons together :c