If you are going to find non-halachic reasons to justify calling Torah behavior “boorish”, I imagine Hashem is NOT pleased.
I doubt very much that Hashem thinks of derech eretz as not being in accordance with the Torah. The behavior of MANY frum people is extremely boorish at times, and they use the Torah as an excuse for their ill-mannered and obnoxious ways. That is why we have a concept of chosid shoteh. My husband’s elderly aunt fell in the street in Boro Park. At least a dozen able-bodied Yeshivah bochurim and men passed her by, seeing she could not get up by herself, and refrained from “negiah” even in a clear emergency. She had to wait for a woman to approach her to help her up, even after asking for help. THIS is YIDDISHKEIT???????? Unfortunately, this aunt was not frum, and the chillul Hashem that occurred as a result of these great tzaddikim refusing to help an elderly lady in distress, was that for the rest of her life she had no respect for any aspect of frumkeit, and offered many a “bracha” to obviously frum people whenever she saw them. How would you feel had it been your mother, wife, sister, or daughter over the age of 12?
On the other hand, I was shopping recently, and had my hands full, and a yeshivah bochur (well past his young teens) held open a door for me and offered to help me with my bags (I didn’t accept, but I was very delighted to see this, and told him his mother brought him up right, and should be very proud of him). Frum does not = bulvan unless you allow it to. A behaima will always find a justification for his or her bad behavior, when there is none. Our mitzvos are designed to make us BETTER human beings, not worse ones.