Yes, that's itA short version of what is does:While the user is...

Yes, that's it

A short version of what is does:
While the user is wearing the earbuds, the "system" (which can include an app as well as the software and hardware in the buds) generates intermittent tones at various frequencies and levels. The user is asked to indicate (eg, by tapping on the app) whenever they hear a tone. In this way the system builds an "audiogram" (a graph) showing the user's hearing threshold at several frequencies. It's repeated for each ear. This information is then loaded into the memory section of the silicon chip(s) in the buds.

This must be done in a very quiet environment so the hearing thresholds are correctly measured, which explains why Rehear mention activating the ANC (ambient noise cancellation) during the test. (I don't remember whether my NUH buds activated ANC during the test but I know they won't commence the test if significant ambient noise is detected).

In a prior life I used to occasionally sit in on meetings reviewing tech papers from design teams to help decide which ones the company would spend money on patenting, so I'll offer the following comments, in case anyone is interested.

The NUH patent is quite comprehensive and obviously written by a very capable patent attorney, which is important. Plus, it was published on 2018-05-18 which is probably early enough to precede competitor patents in this space. Hence Realtek and Rehear's interest?

The lengthy summary section must be detailed enough to allow anyone "skilled in the art" to reproduce the invention. This doesn't allow another company to use it in their products, it just promotes the sharing of technology, otherwise companies would need to be too secretive which would hamper technological progress.
It's quite possible that the summary section suggests a workaround, although it's inferior in the current application. Even if something like this is not protected by the patent it's still considered as having been published so it prevents competitors from patenting the workaround.

Although the summary section is technical and takes up a lot of space, it's mostly the claims section which decides whether an invention is protected or not (especially in the USA) and must be very carefully written. Claim 1 is very general while claims further down the list add increasing detail. I won't try to go through them here. Getting too old LOL.