Assimilation and adaption are preferable. Again, I just don't see anything noble in keeping primitive people primitive so we can study them and feel superior. I would encourage them to hold on to their history and useful parts of their traditional culture.
500 years ago people were fully modern humans who only lacked technologies and knowledge.
So, invent a time machine and give Genghis Khan AK-47s Or the Saracens 155s or the Crusaders Air to Ground capability...okay, that's 700 years ago, but you might get my point. 500 would only take them from the age of sail and draft animals to ICEs and Spacefaring with energy weapons instead of muzzle loaders.
I see great potential for disaster in delivering technologies into the hands of those who are still developing philosophically as well, not to mention the bias of individuals or their naivete seriously affecting the outcome, the future of the planet, the race/species, and the potential for that to have deleterious effects on the whole galaxy. In just the last 100 years (half that, actually) we have gone from being highly tolerant of massive collateral damage to attempt to achieve a military objective to filling JDAMs with concrete instead of explosive and using them as a kinetic weapon to eliminate a targeted building in a dense neighborhood.
Before, we'd have just wiped out the town (shells or bombs), even before air power.
Our philosophies have changed with out technologies, as we became more capable, as we became more capable of destruction. Not to say there have not been beneficial effects, but the same technologies used for peace can be adapted for conflict, and where not, they teach principles which can.
Not to mention the possibilities for proxy wars, planet by planet, system by system, etc.
Behind it all, we still haven't decided the criteria for "advanced".
Who are we to mess with a planet which has existed without conflict, in harmony with its own ecosystem, in a stable society, with primitive technology?
In many ways they are far more advanced than we are, they just don't have fancy gadgets--which might end up destabilizing and destroying a culture which in other ways was far superior.
Let them chart their own course, unless they are a threat to others. Spare them being told how to run their planet by their "betters". We get the same sh*t all the time in the hinterlands...
