I can see two reasons why it would be included here:
The USPTO (and almost all other countries) use the Nice Classification. USPTO examiners will assign classes (using the Nice Classification) to each of the goods and services. The number of classes your application covers (assuming you have more than one good or service) influences the costs for your application.
That particular good was probably included in class 9 which is very wide and generally covers electronic equipment.
But let's say that instead of having "videos of general interest" here, you had something like "videos allowing surgeons to do remote surgery". Is this still class 9, or it is now class 10? Class 10 covers "Surgical, medical, dental and veterinary apparatus and instruments; artificial limbs, eyes and teeth; orthopedic articles; suture materials."
So specifying that this is for "videos of general interest" helps making sure that the applicable good or service is sorted in the right class.
- Avoiding to be too specific
In this case, it's possible that the examiner even asked the applicant what kind of videos would be streamed with the device. The applicant could have been tempted to provide a list, e.g. feature films, documentaries, music clips, etc.
The problem now is that if you provide a list like this, you may fear that somebody else will file an application for a similar mark that would cover something that was not included in your list, e.g. "hardware allowing the user to stream tv series" and argue that the two applications could co-exist because the goods included in the two "competing" applications are not used to stream the same kind of content.
This would be a far-fetched argument in that particular case (especially if the marks are very similar), but the example illustrates the logic behind using something open-ended like "of general interest" (at least when the examiner is happy with that and doesn't ask for more specifications) instead of a close-ended list.