Paramount has chosen to make the audio commentary for Star Trek Beyond available on iTunes, and not on the initial DVD/Blu-ray release, as with recent Trek movie releases.
While it’s expected that fans purchasing the DVD/Blu-ray will receive a digital HD redemption code, this still means that unless one has either Apple TV or can stream their device to their television, fans will need to watch the film with the commentary on a device or computer.
It may well be that in a later release the commentary will be included, as was the case with the Star Trek Compendium Blu-ray Collection when it came out.
This is the new reality, however. It used to be that a movie was released with all of the goodies. But now if a fan wants everything on one format/release with any extras (including bonus items such as mini-ships), one must buy multiple versions from different retailers.
How very Ferengi.