They are asking overgeraed people for easy content. If it was reasonable by "default", just because they can ask for that (no one denies that) they wouldn't be looking for validation on public forums.
Let me pick 7 random strangers to do SM TfB or SM EC with everyone in columi gear, and then tell me that is easy content. HM EC is easy content now, not because it is easy, but because people have the gear and know the instance.
Without knowing the group's skill and the group's gear level, it is impossible to say if 1800 requirement is reasonable or not. So I will stick with my comment, if they are comfortable with 1800 main stat then it is reasonable.