Bart said anonymous in answer to when they were named so untitled - yes.
Brant Pitre and Bart Ehrman will have to argue that one out. I presented Ehrman's altrnative view as one which is held by a well respected scholar but not as my own views since I'm not a well respected scholar!
If we look at the statements about the gospel of Matthew by Papias, Eusebius and Irenaeus, they all say that it was written by Matthew in the Hebrew language, or language of the Hebrews.
Bart's theory that the titles appeared on one manuscript, and were accepted by everybody else, would seem to be contradicted by the additional details in these statements. Papias says that "each one interpreted them (the 'Logia') as he was able". Eusebius says that Matthew gave the Hebrews his gospel when he had decided "to go to others". Irenaeus says that Matthew wrote "while Peter and Paul were preaching in Rome and founding the church".
These separate details would seem to indicate three independent traditions, all of which agreed that Matthew was the author of the gospel with that title.