Nice. This is really normal now, for what it's worth - all of the European makes have moved this direction as well (DoIP over ENET). There's shockingly little documentation about Rivian online, though, probably because emissions regulation doesn't mandate it.
https://automotivevehicletesting.com/vehicle-diagnostics/doi...
Older cars have no concept of such updates.
Happy with my 70s and 80s and early 90s cars.