I think long term scaling will be fine, we can have listings for products and services, each relay has its own board, the cost to have your item listed can subsidize the social aspect of the protocol, like businesses at a mall paying for their space and letting customers in for free. Access to DVMs and DLCs that let you create a MySpace esq profile page will also help. Mid term scaling seems like the tricky part, advertising from a company may require kyc, then relays won't be able to accept money from users.