No, I think this is a valid threat model and a good rebuttal. The evil maid steals the original laptop, replaces it with a second laptop with a look-alike PIN entry screen without an attestation. You enter your PIN, it is transmitted to the evil maid with the first laptop, and your data is unlocked. You would notice, but your data would be exposed.

Now, to be clear, I don't think this negates TPM-sealed disk encryption or TPM-and-PIN sealed disk encryption; they're still meaningfully better than the alternatives (with a passphrase alone, your data is already compromised regardless in this invented scenario, and all scenarios are equally variable to the swiss-cheesiness of UEFI firmware unless it is replaced). But it is a valid model.

What does it matter if it doesn't unlock the disk? It's a different device with a logger. The purpose of the maid is to be evil and steal your pin. The maid has your real device. The only way to prevent this is by you authenticating the device before you enter anything. Look at the heads project (https://github.com/linuxboot/heads).