As a totally separate thing, I don't think BB have to be frustrating.
I think they are without specific modding and a detailed understanding of how to exploit their kit. And I think there's too many teams with too many unique mechanics to expect the average player to learn the intricacies of modding and playing nuBB when they could use that time and brain power and learning to optimize GLAhsoka or some other, more powerful squad. So I think it's inevitable that a large % of the player base is going to find them incredibly frustrating without being able to use Marked.
But it's worth noting that it is possible to mod them the right way and then exploit their abilities in such a way that it's easy for them to win. I don't think I've had to restart a raid run with nuBB anytime recently. My memory could be failing me, but I know for sure that if I did have to restart it wouldn't have been often, nor would it have been a frustrating number of restarts, because I would remember that.
Nope, most of the time, maybe all of the time, I just slap on the mod sets, go in, crush the enemies, rescue the Jedi, and then kick back with a death stick and some Lothal spicebrew.