I should have noted that this was in the context of a group of people who commonly redefine the word to mean something like "chosen family" or, basically, "people I like a lot and would help and would probably expect help from". This word "tribe" would be at best a derivation loosely related to its earlier meaning(s). Given that context, I talked about how I would define it in my own life.

I don't use the word that way myself. In conversation, in that context, I could use it as described above. In general, I'm not much into deliberately redefining words to fit what I wish they meant. I'd rather invent a new one. Less confusion that way.