This one looked like it was a primary hive. Not only did it have proper layers of brood and honey, but it had a marked queen inside. It also looked like it had been in there for quite some time judging by the amount of propolis and burr comb inside.
It’s perfectly “healthy” for them, it will just give to very small and very weak swarms. The lower numbers also makes them more vulnerable to diseases and pests and especially the cold come winter.