Publishers’ inability to sell through their inventory directly to advertisers is a big problem. The publisher “ad tech stack” hasn’t seen enough investment over the last 8 years. Instead, ad tech companies have invested in “proprietary” technology that strips away transparency between the advertiser-publisher relationship in an effort to protect margin. They will probably say otherwise, but that’s the truth. These companies are in for a rude awakening. I don’t think they have a clue about what’s about to happen.