Dynamic volume controls were introduced with release of iPadOS 15.4 onwards. While this feature could be enable or disabled for existing models of iPad, for reasons known only to Apple, the ability to configure this feature is not available for the iPad Air5 and iPad mini6.
Use the Home, side, and other buttons on your iPad - Apple Support
For new models of iPad launched to market after release of iPadOS 15.4 (i.e., the Air5 and mini6), this feature appears to be a fundamental element of User Interface (UI) - with no ability to disable the dynamic controls. The 2022 11” and 12.9” iPads Pro and the iPad10, also released since introduction of this feature, also appear to be unable to disable this feature.
Apple have not updated their documentation to indicate that the 2022 iPads Pro and/or iPad10 are similar in implementation within the iPad Air5 and mini6. Hopefully Apple’s documentation will provide needed clarity in due course.