Maybe that would be a best case scenario. If the hypothetical aliens were like humans but just with more advanced tech we'd be in a far better position to get along OK. If they were infallible, we'd be ruined even if they were benevolent because we'd be inferior. At best, we'd be a charity case for them with no chance of ever being anything else. I doubt if humanity would survive for very long.
200 years of observation would show many things, good and bad. It might, for example, show the hypothetical more advanced people a similar situation to their own history. Or maybe a potential military force. Maybe they've not warlike enough to face threats effectively and would seek to negotiate a deal with humanity to do it for them. Who knows.
I think it would be very bad news, but not necessarily because they'd deliberately eradicate humanuty as a potential threat. I think merely be more intelligent would definitely be enough by itself, leading to humanity fading away from lack of any reason not to.
You might be interested in the dark forest hypothesis for answering Fermi's paradox. Particularly since you understand the easiest way to destroy a planetary species. You probably understand how easy it would be for anyone with the tech for interstellar travel to do and you probably understand how extremely difficult it would be to defend against. If conflict boils down to "whoever shoots first is guaranteed to win", there's a good chance people will shoot first and do so as soon as possible if they encounter another.
My guess is that aliens are, well,
very alien. I go with Haldane's observation that "the universe is not only queerer than we suppose, but queerer than we
can suppose"
I just find the whole concept of intelligent alien life fascinating. Logically, it must exist
somewhere, in some form. Whether the lifeforms would be apparent to, or even detectable by, us is all up for debate.
I'd never heard of the dark forest hypothesis, but it turns out to mirror what I thought. But then I am a pessimistic bugger.
I agree that if, or when, contact happens, it will be a huge psychological shock. Not least, it will profoundly challenge the big religions and their followers.