Zero Tier is not using all the available bandwidth available on secondary network interface

Here’s a thread from 2021 where they state Trusted Paths are deprecated and will be removed in 2.0:

Unfortunately it seems like they didn’t have a strong enough business case to maintain it.

You can certainly still use ZeroTier, you’d just need to rethink how you want to accomplish what you’re trying to do. Realistically, you don’t need to talk east-to-west in your datacenter using ZeroTier, since they’re already on a common LAN. You can just communicate between them using that 10.0.0.0/24 network. You’d simply use ZeroTier to let remote hosts get to the 10.0.0.0/24 network as a managed route.