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Like what? The voluntarily provided User-Agent? The browser is in control of that.

The browser in this adversarial scenario is also in control of the audio context too

Yet it is incredibly difficult to hide the underlying hardware or low level library differences. Not without slowing things down significantly.

Do you, as an end user, know how to change these settings compared to changing your user agent?

From the average user perspective those settings are equally impossible to change, as they neither know nor care that they even exist.