"I want to exchange 1 BTC for USDT", but described the exchange conditions in the topic: "I want to exchange 1 BTC for USDT.
1 BTC = 60000 USDT, so you get 1 BTC.", would this be considered scam?
As a matter of fact, this is called an unfair (or deceptive) trade practice, and it is illegal in most civilized countries You can read more about it here:
Unfair Trade Practice. So, the answer is yes. In general, this would be considered a scam attempt. Even more so in your case - given your account history.