A core part of the theory of evolution is that genetic traits that do not enhance reproduction will be bred out over generations. Since homosexuals do not reproduce, if there was a “homosexual gene” it should have disappeared long ago.
I’ve had some grad students tell me that they were pressured on even some very tangentially related research papers to include how the findings support evolution.
Today, it’s probably global warming... err... climate change.
Also a key requirement is that useful information must be added through mutation, a destructive process.
Those suffering from Down Syndrome don't reproduce, by your logic Down Syndrome should have disappeared long ago as well. Same with Tay Sachs. Evolution does not claim to do away with genetic abnormalities.