I agree. I am Lutheran (Missourri Synod) and although Luther was a great figure in the Protestant Reformation and has his accolades, we are also very careful to note that Luther was not perfect, and not everything Luther said or did is beyond reproach. Where Luther's teachings agree with Scripture, we would agree with him; where they depart, we would remain with Scripture.
To simply throw Luther's quotes around where he was wrong on a subject and somehow use them to support an incorrect position, the original author should also use Luther's incorrect ideas and quotes later in his life about his own German countrymen and the Jews, who were both frustrating him in his later years. If the man was always right, let's use all his quotes, and not just cherry-pick the ones that further one's own incorrect views.
Luther wasn't infallible, and nobody but God is infallible. No person save Jesus Christ (God the Son, in the flesh) was infallible. Luther was wrong in his views on certain aspects of Mary. He was wrong on other things as well. We don't point them out to beat him up and savage him because of it, but I point it out because the original poster is using his incorrect quotes to further buttress his own incorrect viewpoint by saying even a Protestant believes what the Roman church teaches.
Are you not guilty of doing the same thing? Cherry-picking quotes to support your position? No one ever can claim to know who is wrong or right about Mary, and to claim otherwise is irresponsible. I did not read any reference to the Roman Catholic Church or that he was pushing any sort of agenda.
If Mary was held in such high regard by God, as the only person ever to bear His son, certainly we must hold her in the same regard. This is in the Holy Scripture. It is through Mary that Jesus came to this world by the power of the Holy Spirit and by the Will of God.
Please don't get so angry, or argumentative. In the end, there will be only one truth. We need to be supportive of other Christian faiths and not denegrate another. We get that enough from other sources. We are one body, with many different ideas.
Among other things, I was taught in a Missouri Synod school, with male teachers, no less (Reinhold Arkebauer, Luther Kollander, and Adolph Stahlecker...does that confirm my background?)