Amazon has quietly built an advertising juggernaut, and Prime Video is at the heart of that growth. The tech giant reported $17.1 billion in advertising revenue in Q1 (that’s more revenue than Warner Bros. Discovery and Paramount combined), with CEO Andy Jassy telling Wall Street the the company had $70 billion in ads revenue over the trailing twelve months. In fact, Amazon execs now say that Prime Video is profitable in its own right. Prime Video, of course, made a fortuitous call to flip on advertising for all of its users last year, giving them the option to pay more to opt out. Most, of course, chose to keep watching with ads. Now the video platform is planning to leverage its newly year-round slate of live sports to grow that pie even more.…