It`s all fun and games and hugging until the bear rips your arm off. Then it`s not funny anymore.
Might come down to intent on the part of both man and animal. Perhaps most of all whether or not they sense fear. Though I don't believe such considerations can be consistent enough to determine relative safety either.
But it's fascinating to see it happen when it begins- and ends well. The point being that there are any number of species that may interact well with man on a limited basis beyond merely domesticated animals. - With no guarantees.