Certainly on point for the most part here. I agree they are likely just posting to post too. However if you asked me whats the best crypto exchange for bitcoin selling, Id tell you Coinbase. I am not a huge fan of the company, but they are the cheapest for US citizens by far. They are very user friendly and always have been.
Coinbase is one of the best one but until now, they are not operating buy-sell service in most of the countries. If it comes to trading bitcoin, I would suggest Binance, BTC/stable coin pair. However, for alt trading, there are bunches of trusted sites. Just follow one strategy, don't put your balance in any exchange.