Good news guys! Collabora gave us 6.14 kernel with full Radxa5B+ support: https://gitlab.collabora.com/hardware-enablement/rockchip-3588/linux/-/tree/rock5b-plus
As far as I tested it, everything works out-of-the-box! 2.5G eth, WiFi, BT, WWAN, NVMe
This is true first class experience!