Martinstahl is clearly lying. He said the site started in 2007 but a quick google search will tell us that chess.com started in 2005. Also 20 years is an estimate for the time. So I have proof that Martinstahl is lying (there are more lies).
Prior to 2007 the Chess.com domain was owned by a company called Aficionado that sold Chess training software called Chess Mentor. It wasn't a playing site and didn't have anything else.
The site you're on today did not exist until 2007. Maybe go check out the site history posted by the CEO and co-founder @erik before saying someone is lying.
https://www.chess.com/blog/erik/why-and-how-i-started-chess-com
In particular
https://www.chess.com/news/view/building-chesscom-part-1---getting-started
Martinstahl is clearly lying. He said the site started in 2007 but a quick google search will tell us that chess.com started in 2005. Also 20 years is an estimate for the time. So I have proof that Martinstahl is lying (there are more lies).