Because they don’t like being told the truth.

Deuteronomy 22:5

5 A woman must not wear men’s clothing, nor a man wear women’s clothing, for the LORD your God detests anyone who does this.

There are many more:

Deuteronomy 23:1

1“No one whose testicles are crushed or whose male organ is cut off shall enter the assembly of the Lord.

I could go on as there is much more, like in the New Testament about who gets into the kingdom of Heaven, but this sin has been around a long time.

Eternity is a long time. Ignoring that won’t make it go away. They hate God and are going against what the Bible says at every turn.

It’s going to catch up with them and there is no running away from judgement. That is why they hate God.