I think he is promoting his own creation, as I also received a PM from him with similar content. He thinks that I'm going to fall to this other Bitcoin clone. Even if I am mining, I am not going to risk switching to an unknown coin because I could end up paying my bill with a huge loss. Unless the developers of this coin are going to list it on big exchanges like Binance and OKX and the profitability is 5x or 10x higher than mining Bitcoin. I'd be happy to switch my solo miner to this coin, but it's not even listed on any exchanges. There is one coin called BTCC in Coingecko, but it is an exchange with the same name.
Which means he has sent out a couple of those unsolicited PMs to other members too. he is most likely going to be banned if the messages are reported to the administrators. People are done mining enough shitcoins; i don't think they can fall for this, especially when it's listed nowhere.
Worse still, the coin has no use case or uniqueness. It's just the same recycled garbage over and over again, which means even if it was listed in any exchange, the price would just keep going lower and lower until nobody was interested in trading it