There is already work on a Gran Turismo 7 SimTools plugin that decodes the encrypted UDP telemetry payload from Sony’s Gran Turismo 7 to be used for motion platforms via an external PC (similarly to how Forza Motorsport 7 works with D-Box with a second PC, although there’s a workaround for that).
Hopefully D-Box can somehow work with on this as well, or hopefully SimTools can one day support the D-Box system.
https://www.gtplanet.net/gran-turismo-7s-secret-api-discovered-enabling-motion-rigs-telemetry-info-and-more/
https://www.gtplanet.net/gran-turismo-7-telemetry-data-now-available-via-open-source-software/
https://www.resetera.com/threads/gran-turismo-7%E2%80%99s-secret-api-discovered-enables-motion-rigs-telemetry-info-side-dashboards-and-more.612246/