No there a number of fiat based v4v sub based platforms that seem to work. We just don't have a large enough user base for sats based v4v yet.

I will say, ultimately I think we land on some hybrid of monetize attention/v4v. I think you can do it so it doesn't erode user experience. Take the SN leaderboard as an example. SN could sell sponsorship of the leaderboard to companies thus funding the daily rewards pool and helping keep the v4v ecosystem going.