There is smart technology on phones that calculates the delay in audio and it delays playback of the video feed to match the audio feed. This is possible because you can buffer a video. With a game you can’t buffer the gameplay as it all happens instantaneously and it needs to constantly watch for your inputs, which likewise can’t be buffered.

There are some Bluetooth codecs that do support low latency so I don’t want to say this is a universal Bluetooth problem, but it is a pervasive one. Cheaper Bluetooth earbuds and even most mid to high end ones prioritize sound quality over latency and therefore don’t support low latency codecs. Likewise the transmitting device ALSO needs to support the codec, so even if you found earbuds that work, the device isn’t guaranteed to be compatible. For the consumer this is a very confusing process and I personally think Sony just didn’t bother with it to avoid the confusion…and to push their own standard (PS Link) and sell their own headsets because they are a profit oriented business after all.

If you want, download the remote play app for your phone and test it out yourself to see what I mean.