I’ve done plenty of CQB drills with both. Realistically there is not a ton of difference, but I expect that the AR is faster, particularly in a 16” midlength configuration, or running something like an A1. I’m a lefty which is a benefit for running AKs, but the AR just has a lot less reciprocating mass, the reciprocating mass is almost all inline with the shoulder, and the safety is faster. The difference in speed goes down if you run the AK eastern style aka don’t try to actuate the safety on and off when not actively engaging target, but the AR still has less mass. Reloads are faster with an AR as well. 5.45 has less recoil than 5.56, but I don’t think that’s as important as the improved ergos and lower reciprocating mass of the AR. If you incorporate night vision and IR aiming devices, I think the AR pulls even farther ahead.
Overall I think AKs have a higher floor due to the easy to learn manual of arms, but ARs have a higher ceiling due to inherent advantages in ergos and operating system. Realistically you can be very fast with either as long as you train. Standing still and dumping mags, I’m not sure there is a huge difference.