It's been around for a while. Even assuming people beyond the FOSS/Fediverse kind of communities (which I think experience shows is a fairly niche community) are interested in this, I can see a raft of practical issues around (for instance) the bandwidth required for the endless exchange of personal data (assuming that services don't store the personal data provided by the data provision service). However, I can imagine limited versions that might be practical and be able to gain traction (I, for one, would be happy to never have to read and click on a cookie policy again) and I think the policy verification would work for those as much as for the more extreme data pod visions.