WireGuard ignores Routing-Mark

[Guscht]

I was reading his method here:

RouterOS blatantly ignores pref-src. Can this really be a bug?

I was planning on writing out an example, so just for your reading pleasure: the official “rabbit hole solution” to multi-wan wireguard hosting. We have two WANS. For this example, the two WAN connections are actually EoIP tunnels to another router. The base configuration is: Interfaces: /interface eoip add name=eoip-wan1 remote-address=[other_router] tunnel-id=10 add name=eoip-wan2 remote-address=[other_router] tunnel-id=20 Addresses: /ip address add address=192.168.111.10/24 interface=eoi…

But he lost me on the stage:

Create a bridge with a /30 address:

/interface bridge
add name=br-wg protocol-mode=none

/ip address
add address=172.16.10.1/30 interface=br-wg

I see no connection between this bridge and the WireGuard-Instance?
And the IP “172.16.10.2” in his SNAT rules. What does this?

But if you tell me this is “by design” so, I can live with it.
I think the “routing rule” solution is much easier and resilient (at least with static-public-IPs) than some bridge and NATing.

But I’d would still like to know why “Mangling” fails but Routing/Rules works? As long as under Routing/Settings Policy “User” is above “Main”. AFAIK Mangling and Rounting/Rules are almost the same? Mangling is a more “sophisticated” way and Rounting/Rules simpler?