As interesting as living in a tribal fashion is, and believe you me that I have thought about this very topic extensively in my younger days and even sort of had my own tribe made up of my chosen family. I am a bit too selfish to fully embrace a tribal lifestyle, only in that I value my privacy and I enjoy ownership without coveting what other people have.
If it is greedy to want to settle on a piece of land, own a domicile of my choice and enjoy my life without much outside interference, then I guess
I am that. It is a different world than when tribes of that nature existed as a dominant force. This contemporary world has no room for tribes and the mindset of people who are not born in the African jungles nor the Amazon is too ingrained with our lifestyles to truly embrace the mentality of traditional tribal living.
Sure there are some who would do it in a heartbeat because they don't fit in the majority society and I give all the possible respect for that so long as they do not press their views and lifestyle choices on me. By that I mean berating me for my own personal choices and disrespecting me, much like semi-militant vegans/atheists get whenever they encounter a carnivorous human/person that believes in a god/many gods, etc.
Its an interesting idea on paper but it is difficult to actually put into practice. Were there a worldwide disaster and the infrastructures fail, then we may have to revert to tribalism to survive. And many, many folks will surely perish because they're not able to handle the stress of a world changing event.
I also feel that said tribalism is one step away from anarchy as the OP pointed out without acknowledging it outright. People are inherently covetous, its not a trait suddenly introduced by an outside force. However when one lives a meager, bare existence, there's little to covet from a neighboring human. However introducing the idea of wealth sparks said covetous nature. It may not even need an outside force to do so. Say a tribe member finds a shiny yellow nugget in the stream. This person, male or female matters not, takes said rock home and puts it on display or just admires it. Another tribal member shows up, perhaps a sort of bully (and yes bullies did exist in tribes) sees the rock and instantly wants it for himself, because its different and special and unique.
That was just an example and more of a hypothetical story. But greed/covetous nature is seemingly hardwired into the human race. However some of us are able to knock it way down by sheer willpower. Even animals do show greed and jealousy, its not a trait that only humans have.
TL;DR - Sure in the right conditions people could live in a tribal society, and myself could as well if that was the only option of civilization. However I know that people can turn covetous with ease, and a tribal sort of loose "management" (I have a better term for that but I can't recall) can easily degenerate into anarchy.