OK, OK, he doesn’t say that. But it is implied in his latest interview with PC Gamer.
Garriot is referring to the past in that everyone who made games either was a computer programmer or an artist. Those were the first game makers.
Since then, generations of kids have grown up on gaming. They feel they have a ‘video game’ buried deep inside them. Boy, oh boy, they want to get into gaming! However, they have poor art skills. They also aren’t great at programming. Therefore, they’ll focus on ‘design’!
I definitely think Richard Garriot is on to something here. I would even go further and say these game designers are often wannabe writers who can’t get people to buy their work.
If I understand Lord British correctly, even he is saying The Hardcore Must Be Destroyed!

OBEY: The Hardcore Must Be Destroyed!