The argument isn’t just around content, it’s around hosting. If Google is sitting there scarfing down Reddit’s data, that costs Reddit in server time. That can get extremely expensive. So yeah, if Google is going to train an AI that Google will profit off of, it should pay Reddit for server time.
I was part of that! I was on a team that made a web site that visualized the effect on poverty levels on a county-by-county basis when the minimum wage was at different levels. It made the need for a split minimum wage obvious, since the minimum wage that is necessary for metro areas is inappropriate for rural areas. Rumor has it that the legislature used it in the decision making to some degree.