The best exchange to buy and sell Bitcoin or any cryptocurrency is Binance Exchange or Cuckooin Exchange which have complete P2P transactions. Where your ricks are very less but in this case if you contact directly on telegram then you can definitely face risk.
You are right about Binance but most people are only seeking options like these because they don't want to trade on exchanges that require KYC. AFAIK only decentralized exchanges are the ones that don't require KYC for p2p trades, otherwise every centralized exchange if not at the start then after some time starts to require you to do KYC if you want to do p2p.
Besides this fact, you are totally right about the OP I don't see any positive feedback from any dt1 or dt2 even from any other member as well. So it raises concerns but he/she also has not received a negative yet so maybe he is not a scammer at all but why not giving feedback maybe he did not received any order yet from this platform although it will be shocking for me if its true as he is here since 2015.
