No, you are missing the point. The moral history of the world does not terminate in the present. You are basically arguing that the modern consensus is the only acceptable opinion to hold. 50 years ago the modern consensus was that gays should not have rights. The person filling your shoes then would have said "It's unacceptable to discuss giving Gay's rights, we all know it's wrong and abominable, anyone with that opinion should be driven from their post".