Now all this is literally saying is, "there is nothing we can do... Good day sir"
That's exactly what they are saying, sorry!
Though, is there really nothing I can do, given the blockchain information at hand?
In terms of getting your coins back, your chances are slim. There is no centralized authority or customer support in Bitcoin that can help you and Coinbase can't do anything either because the coins were never deposited in one of their wallets either. Use this bad experience as a learning opportunity download software from official sources and verify its authenticity.
Does this perhaps look like I fell into a scam, as some people have quoted, and thus getting in touch with the authorities would be to no avail, given how the Blockchain works?
Looking at the info hosseinimr93 found, it looks like you were a victim of a scam, yes. Finding a person behind a bitcoin address is a difficult task otherwise people wouldn't use Bitcoin. If the scammer sent those coins to an exchange where he performed KYC, it would be doable. But the exchange will never give you that information. You would have to get law enforcement involved and the sum that went missing is simply not worth it. It's around $800 worth of bitcoin. The cost of trying to recover it and finding the culprit could be bigger. Like Lucius said, too much time has passed.