It’s the same for 3.4.5 - with 99.9% certainty, that version won’t be fixed as it still used the old PX4Firmware drivers which are harder to work with. Probably 3.5.0 won’t have it either (as we want to release it as soon as possible), but a patch should be easy enough that it will most likely be fixed in a 3.5.X release.
Just to explain a little better: the Pixhawk only has one external I2C bus and that’s what the team is used to; now with PH2.1 the I2C bus that was internal in the Pixhawk was made external too and we are still adjusting to that - at the same time we changed to using our own drivers (which are now shared with Linux boards) so we can take our time to have everything working as expected by all users. And yes, this affects all of ArduPilot vehicles.