https://bitcointalk.org/index.php?topic=5289066.0Low 40's is normal for the 1080ti and it will only get lower due to a known bug suffered by the 10x0 series excluding the 1070ti where it was fixed.
1080Ti has gone from 55 to 43mh in 5 years and 1070 has gone from about 33mh to 25mh.
I understand your point perfectly but I really want to know why these cards lose has rated over time, I am guessing this happened because of Nvidia lack of support for the graphic cards through support drivers or there is more.??