Returning to this thread, I have come to strongly oppose the idea of charging fees using this opcode. I understand the temptation of the UX win from displaying one transaction cost to the user, but it’s quite sneaky to charge callers a fee there. It fights a decade of user training around the expectation that their wallet shows them gas separate from value, i.e. “gas is the unavoidable thing I pay Ethereum, and value is where my fees live.”
If the opcode existed and wallets would easily, transparently show every user “this transaction will cost X gas because of Ethereum plus Y gas to support your favorite developer” this would be a different matter, but we know that’s a reach.