There are several issues - one is that patents are given for specific ways of solving a problem, sometimes very narrowly different from other ways of solving a problem, not for a result. There are usually many ways to achieve a result.
Another, that you bring up, is “field of use”. That comes into play in method claims but not usually in device or systems claims. A claim to a “thing”- system, device, machine etc. is infringed by another thing (that fits within the claimed definition) just sitting on a shelf in a box. Intended use is not traditionally relevant. If a device for any intended use fits the words of a claim, it infringes. In your case the preamble of a system claim says “system for mixing or compositing in real-time, computer generated 3D objects”. At least in the US that would not usually be limiting to that use but just taken as a description of the thing, not requiring actual specified use to infringe. Read it as “capable of being used for”.
Method claims can limit field of use. A method for getting rust cleared from a screwdriver that had a step “provide a rusty screwdriver” would be limited to that use.
Another example would be a back scratcher configured exactly as a small garden rake but claimed in a method for scratching one’s back. Assume the garden rake is known - the backscratcher as a thing could not be patented, but a method of using something of a certain shape and design (small garden rake) to scratch your back could be. Someone with a garden rake couldn’t scratch their back even though they owned the garden rake. Note that a small garden sold as good for use as a backscratcher would be committing contributory infringement unless they had a license.
Something being covered by a patent owned by its manufacturer does not mean it, or its use, does not infringe some other patent owned by a totally unrelated entity. Of course it is possible a manufacturer has licensed relevant patents of others.
The patent you link to is not only described as used for broadcast. Gaming and other entertainment uses are mentioned.
As mentioned in another answer, the Intel device works in a way that doesn’t fall under the claims of the sited patent. It has two cameras in total while the claims require a main camera and two additional cameras to do the position determination another with other inertial sensors. Some uses of the Intel device could theoretically infringe method claims in one or more un-sighted, unknown, patents.
If someone bolted the intel device to a “film camera” and used the combination as described in the method claim you might get the quality image you need and only use the intel device for the position information. Then you might infringe.