I can't speak to why he isn't supporting that concept, but it'd likely substantially constrain growth. Many current and potential users would simply opt not to

I can't speak to why he isn't supporting that concept, but it'd likely substantially constrain growth. Many current and potential users would simply opt not to pay. Others would cut down the number of accounts they maintain. And it would also potentially change the overall demographic of the user-base, even if the charge was nominal.