I’m running pangolin for a couple months now and instead of newt I use my router WireGuard Client in a VLAN.
Any „wanted“ traffic is then routed via DNAT/firewall to my home server.
It’s not simply diffusion complexity. A lot of cellular transport is dependent on directed transport via the cytoskeleton and myosin. For example a 1m long neutron would need years to move proteins from one end to the other if it just relied on diffusion.