I’d agree they should be left alone in their natural habitats but many animals do adapt just fine to a life in captivity. From what I have read Octopus are solitary, primarily nocturnal animals and often close themselves into rock dens during the day. Kinda like brainac introverts. lol
A very small species might do fine in a captive environment, a larger species no.
Females die after breeding at 1–2 years of age otherwise they only live 3–5 years so this is not a long lived animal like a cat, dog, goose, horse, parrot or tortoise.
“Boredom” is not a concept animals understand nor think of. Boredom is a human construct. Yes, animals need stimulation to be their healthiest and happiest, and some animals more so than others. Rabbits not much, dogs and parrots a lot.