Do the Apple AirPods have audio delay due to bluetooth?
There is zero concern for music and videos since the system compensates for audio delay. Same for many games since as long as the visual and audio tracks start at the same time (buffering enough content for each to start and then hoping the new content delivery / creation can keep the buffer from emptying).

Now, technically speaking, the laws of physics and the limited processing power of the CPU/chips that encode/decode the audio ensures there is a delay - but it's not on the order of a second. Subjectively, this isn’t a problem for me until I use airplay / WiFi and even then it’s nit horrible but the lag is noticeable. But I also can’t argue if someone else has a subjectively different experience and the lag isn’t acceptable to them. 

The codec and stream of the bluetooth chips means that the sound needs to be buffered, encoded, transmitted, decoded and then sent through the amplifier.

There have been some nice attempts to scientifically measure this - http://stephencoyle.net/airpods/

The raw data says the measured latency of wired headphones is around 85 ms and AirPods are around 256 ms. My personal impression is the AirPods are more in the range of 120 ms delay and almost equivalent to wired earphones. Also, I'm fairly certain that Apple corrects for video playback if you use the API since I've never ever gotten the feeling that videos lag when switching from AirPods to EarPods and back on Apple devices and Apple audio devices.

Same sort of synchronization is being done for the HomePod setup where millisecond sync and offset is going to be used to synchronize and phase the sounds for multiple bluetooth playback speakers spread around a room, but that's a far easier task where you can buffer all the sounds and then play a delayed and perfectly synchronous to the phase of the sound waves - as opposed to having a low latency audio interface.

You'll want custom hardware for that like the Universal Audio Arrow line of monitor hardware if you are performing live or making millisecond measurements.


https://www.uaudio.com/audio-interfaces/arrow.html


The only case where I've seen lag as a legitimate problem is musicians with split second timing needs or scientific measurement apps. I've also heard of AirPods and iPhones needing a restore if they get stuck or some process is running amok and otherwise slowing down the processing of audio.