
Thinking of the most interesting case, a discretionary interaction, a more advanced society could probably easily identify ways of preventing pain or hardship in a less advanced society with their more advanced technology, spreading the smallpox vaccine would be an example in the human case.
If there were no existential risk to either civilization, and the more advanced society could adequately communicate with the lesser advanced society, to what degree if any should an advanced society be morally obligated to share their advanced technology with a less advanced society?
Presumably high up in the most likely example of an advanced society’s goals would be the furthering of knowledge and technology, and presumably this could be better accomplished with additional agents. So an advanced society would be more rather than less likely to share advanced technology, most likely overtly, even if it could adversely impact the culture of the less advanced society.
How the technology would be shared could be an interesting question, if the possessing society were advanced enough presumably it would be shared non-pecuniarily. Identifying which technologies should be shared could also be an interesting question as there will likely still be some competition for status and resources but probably nearly all technology could be shared as lesser advanced societies advanced to parity.
The foresightedness and cohesion required to consider the possibility of encountering other societies and have a universally agreed upon policy for this situation would seem to be one early mark of an advanced civilization.