I can imagine that being the case in single player... like many games these days it's just not designed for that. If you had yourself a crew on Discord or whatever it'd be a lot better... so not really the game's fault...
Also at the moment it's true that the game is pretty much PVP all the way, but I'm hoping what they are going to do eventually is introduce some more PVE elements which are too difficult or impossible for a single crew to complete alone, which will necessitate forming a sort of nervous alliance with one or more other crews (and all of the possibilities for double crosses and backstabbing that that brings)
The PVP stuff is where it's at though, it's so funny... the other night a mate and I were slooping it up and both on an island when a rival sloop we didn't notice had pulled up right next to our moored ship and started blasting at it... We scrambled aboard and dropped sail, speeding away and repairing the damage and then turned back after the attackers. After a few criss-cross trading of shots I guess they decided to run away so we chased them along for a good 10 minutes or so. Eventually my shipmate was able to cannon himself ahead of them, get aboard and drop their anchor... then as he kept them busy on deck I rolled up next to them and obliterated their ship... They had tons of stuff on board and were mega-salty about it all in chat - one of them was yelling "You're just a couple of viiiiirgins!!!" as their ship sank - was hilarious