I’d like to put in a case for leaving chainId replay protection up to the invoker with a tangible example where cross chain replay by design is quite useful
A powerful underexplored pattern with 3074 is to use an invoker as the primary source of authentication logic. This can be done by crafting a one-time AUTH message with no replay protection and generating a synthetic signature so there is no underlying private key. Now that 3074 supports native transfer this effectively allows for singleton SCW implementations and near-full SCW functionality without deployment required
Enforcing chainId severely limits this pattern as a given account generated this way must be chain-specific, causing horrible multichain wallet UX.