The market and the history of the game is precisely the reason they became like this. It's hard to build a profitable server platform that can compete with what

The market and the history of the game is precisely the reason they became like this. It's hard to build a profitable server platform that can compete with what's already there. Engines are already very advanced, especially on the open-source front. Free resources are plentiful. Bookshelves are already crowded and chess-related articles probably don't make that much money. To make a successful app, you'd need some name recognition like Magnus. Coaching services are probably a no-go as well, since a professional player interested in that can always get a lucrative deal with chess.com or chess24 if they are high-profile or simply quickly get clients on their own and not have to pay a percentage. All that is really left is targeting people who can't or won't perform even the most cursory research relating to their purchases.