If this explanation of what playing with others in an MMORPG is supposed to be is not enough, I don't know what would be. I couldn't have said it much better myself.
As with regards to the squadrons playable in dungeons, it is not for all dungeons. So new contents would still be played with actual players. Like what others have said, soloing a dungeon is already existing so having your squadron with you shouldn't be an issue. There are players out there who could probably use the squadrons to practice doing dungeons which may increase their confidence to play said dungeons with actual players.
Sometimes one just have to check what benefits a new feature can offer instead of bashing it down before it can even be released.
