Finally the wait is over and all iPhone owners will get a PIP for Youtube.

Everyone watching TV programs can exit the app with a simple swipe up from the bottom, and the iPhone/iPad will return to the device’s homepage, while the video will continue running PIP.
The window can then be resized or moved around the screen.

If you are a YouTube Premium subscriber (both on Android and iOS) you can enjoy the new feature right now. Google did reveal it is planning to allow PIP for everyone in the United States, but it isn’t available yet.