This is not true. To my knowledge there is nothing in the game that you can’t solo.
But there are efficiencies in playing with others. 2 players can kill a creature twice as quickly, and they both get drops. So this is a 4x multiplier (irrelevant of current or future balance.)
Not true. We’ve said many times that Boundless can be played by solo players.
What isn’t solo’able at the moment?