Comment by Jakob

Yes, this is unfortunately still the way and was very common back when iOS Safari did not allow embedded video.

For a fast start of the video, reverse the implementation: instead of downgrading from Websockets to polling when connection fails, you should upgrade from polling to Websockets when the network allows.

Socket.io was one of the first libraries that did that switching and had it wrong first, too. Learned the enterprise network behaviour and they switched the implementation.