Realtime updates (if you're not using Websockets) are usually done with long-polling, for which 30 seconds is perfectly acceptable. Socket.io, for example, uses a default of 20 seconds [1].
Streaming music and certainly video are generally delivered as chunks, with a few chunks per request that don't require long connections [2].
While I agree that a 30 second limit is to be expected in order to conserve resources, saying long requests aren't needed shows a lack of imagination.