This could be observational bias but as far as I can tell Battlegrounds teams really don’t feel like they are randomized.
It seems like when the same 8 people queue up, the teams don’t change at all and when 1 or 2 people swap in/out the teams end up being very similar.
I’m not sure if there is some sort of MMR or team balancing going on that causes this to be the case but if there is a system is in place it doesn’t seem much better at balancing the teams than just randomness.
Regardless, the lack of randomization makes it so that if you get an unbalanced match up, you keep repeatedly getting that bad match up. Additionally, it makes it difficult to enjoy queueing for more than a few matches in a row because every match just feels the same with the same enemies and the same allies.
I’m sure the ability to queue in pairs to be on the same team doesn’t help with balance or the randomness either. I honestly think queueing together should allow you to make sure you both end up in the same match but it should have no influence on if you end up on the same team.