Or, perhaps not. Perhaps one of those who were contacted will leverage that prestige to secure power. Or, perhaps panic-driven crowds will massacre those who we contacted. Perhaps, even with the best science, we'll spread a virus or two. A first contact situation is, by definition, unpredictable.
When we are talking about non-technological societies who may not even have invented writing, and who have not developed an awareness that other cultures exist on their planet or elsewhere, who in fact do not know they are on a planet, the chances of even a minimal contact having an inadvertent impact exist.
Those possibilities exist regardless of how advanced the society is. One of the most inane assumptions behind Prime Directive boilerplate is that
any and all change a society undergoes is somehow unnatural disruption. That's total BS. Every society is constantly undergoing change. Every society has different factions within it competing with each other, jockeying for status.
The myth is that any change is caused purely by the visitors. That's actually rather racist, because it denies the agency of the contactees, their ability to think and act and choose for themselves. In reality, when an outside contact triggers a change within a society, it's because an existing faction within that society capitalizes on it to advance its own agenda. If it hadn't been the outside contact that triggered it, something else might have.
Well using a real world example, we know that in Cortes conquest of Tenochtitlan, his presence shaped and interfered with native socieities in the region. People often forget that his victory was forged with the assistance of groups hostile to the Aztecs. Many who were willing to use the Spanish against the Aztecs.
But that's actually a good example of my point. It was the Mexica peoples themselves who did the bulk of the work overthrowing the Aztecs. All Cortez did (at least initially) was provide a catalyst for a change that was burgeoning in the society already.
Of course, Cortez is a bad example, because he was deliberately
trying to change the status quo, namely by taking over the whole ball of wax. I don't for a moment deny that an outsider making a deliberate effort to impose change can cause great harm and disruption. My point, in fact, is that when disruption occurs, it's
because of the intentional desire to disrupt, reform, or eradicate the native culture -- it's not an inevitable result of contact. Historically, contacts with the intent to conquer, convert, or assimilate have been damaging or disastrous, but less aggressive contacts, interactions based solely in trade or exploration, have been less damaging.
Do those contacts bring change? Very possibly, even probably. But it's a mistake to assume that change equals contamination. One of the biggest errors that people tend to make about indigenous cultures is that they way they were at the time of contact was the same way they'd always been since the dawn of time. That's crap. Change is normal. Every culture goes through changes that can be triggered by any number of internal or external factors. So to say that you shouldn't talk to an alien culture because it might bring changes is not a good reason at all. Even a warp-level culture can be changed by its contact with you, or you could be changed by contact with a pre-warp culture. Even without contact, you and they will undergo changes within your own respective cultures. And you'll adapt to those changes and go on with your lives -- because that's what cultures do. They don't remain absolutely static and then fall completely apart at the first hint of change.