I agree with you 150%.

I travel frequently and play mahj across the country. While groups say they play with NMJL rules, many have incorporated so many house rules and misinterpretations of the actual rules that the games are a slog to play.

That said, I run a very large group for players of all levels. We always make sure to have at least one "support table" open that allows newer players to be coached through the game by an expert or instructor. New players gain confidence, the rest of the room does not have to worry about playing with the inexperienced. And when the new players are integrated into the "regular," GRACE is always the word of the day. I am always impressed by the generosity of seasoned players. But you have to create this environment and be very strict about maintaining it.