The blog post being discussed here is about handling a crash in "waybridge" instead, so to speak, and having this ability in Wayland itself instead of requiring an additional abstraction and protocol.
Arcan can use multiple waybridge instances, e.g. one per client, to get some isolation between the clients (from the post), but it does start to sound a bit heavy perhaps (I don't know much about the inter-Arcan IPC though).
Cool stuff, though.