Ad revenue is mostly tied to sales people talking with big companies, addressing their issues. For example: Southwest airlines has a huge number of advertiseme

Ad revenue is mostly tied to sales people talking with big companies, addressing their issues. For example: Southwest airlines has a huge number of advertisements across the internet. But Southwest doesn't want these advertisements to appear next to airport disasters. This kind of "custom request" is the bulk of $Millions+ revenues. You need to constantly cater to these company's seemingly arbitrary requests as they try to protect their brand. Twitter fired the team that did this. And when they did, the big companies that care about their image left.