I am still curious to know: why do people buy usernames? I have read about something similar to this before, but I couldn't wrap my head around why anyone would have to pay such a huge amount of money for a username. Could it be to buy the identity of the original owner of the name and use it to scam people or for any other reason best known to them?
Afaik, they would trick you into transferring ownership of your username and later use it to scam others connected to you, since no monetary transaction is involved here.
Oh, I see. My take on this is that whether the offer from the scammer is genuine or not, people should generally desist from selling their usernames on Telegram. It might actually be a smooth transaction between the buyer and the seller, but others who know nothing about this exchange might become victims by trusting a total stranger, thinking it's someone they used to know. When these strangers come to our DMs with this kind of offer, the response should be "no, I don't want to sell my identity" and not just "oh! This dude wants to scam me." Even if the offer is genuine, don't sell. This way, we would save lots of people from becoming victims. Unfortunately, some persons would be too greedy to even think about the negative consequences of such transactions.