That's harder in practice than you make it sound. Firmware updates for Intel ME are handled through OEMs, it's not a file that Intel publishes that an interested person can go to their website and download. The article claims that such a patch has been released to OEMs but is being kept under wraps, which might make it hard to determine when it actually ships in a downstream update. Even if you have a file that you know contains the binary blob of updated firmware, reverse-engineering it to determine what it does differently compared to the previous version is very much non-trivial.