all new ship designs have no more family members, no zoos, only combat, Sovereign, Defiant, Akira, etc... The days of zoos and barber shops are gone. Lol
Well, we don't really know that, or probably ever will, sadly. It does seem in ST8-10 that the
Sovereign is set for combat as Picard laments "Remember when we used to be explorers?", and clearly
Defiant is a warship, but we never saw inside
Akira,
Steamrunner, etc. For all we know, after the Dominion War, Starfleet returned some ships back to family-capable.
Voyager seemed to adapt very easily to being in a situation where families and children were on board.
Like a barbershop, those amenities aren't unnecessary frills, (or worse, just "smoke-and-mitrrors" to fool outsiders to the ship's real power), but helpful for the crew during long missions, whether combat or exploration. Just like modern naval carriers having gyms, movie theaters, lounges with Xboxes, an arboretum, a bowling alley, and lounges would be a necessity. Like in "Galaxy Quest" when Allan Rickman's character is asked right after a battle, "Where are you going?", he snarls, "To see if there's a pub on this ship!"