Mixed sexes in shared quarters?

[Tosk]

If it's a bunch of bunkbeds like WW II era enlisted quarters, maybe they could share, but just maybe.

No maybe about it. We see two men and a woman sharing bunks in Star Trek 6.

 

[Tenacity]

Males of the Dah'ssss species only appear female.

 

[Kor]

There are already real-world military settings that require men and women to bunk together. Presumably, all the kinks would be worked out in the next few centuries, especially since humanity supposedly becomes so much more enlightened and advanced in that time.

Kor