I like how Luke says "me as well" strongly suggesting that there were already previous written records of"the word".No, Biblical scholars are not pretty much in unanimous agreement on 'Source Criticism'
The idea that the Biblical Gospels were not written by who they are attributed to by the Early Church, is a very weak liberal argument
As for Luke,
Luke 1:1-4 "Inasmuch as many have undertaken to compile an account of the things accomplished among us, just as they were handed down to us by those who from the beginning were eyewitnesses and servants of the word, it seemed fitting for me as well, having investigated everything carefully from the beginning, to write it out for you in consecutive order, most excellent Theophilus; so that you may know the exact truth about the things you have been taught."
Luke and the person Theophilus indicate that the Gospel of Luke was written prior to 70 A.D.