Because the INDIVIDUAL is the social unit of consequence in a secular democracy with the FREEDOM to take LIBERTIES with what – or who – makes them HAPPY –
The DISTANCE BETWEEN church and state is the measurement of individual freedoms – of which – EQUALITY is the supreme right above all other rights, for everything else is a choice of the individual
We do not choose what demographics groups we belong to as individuals – so discrimination against people who are less than 1% genetically different from yourself is not merely willful ignorance but unadulterated hatred of your fellow humans.
and hating someone for their choices of expression or how to live their lives is just regular ignorance – because it is down to the individual to be the expert of their live and existence
imposing your will and beliefs onto others or attempting to make your religious beliefs into law in a secular democratic nation is ILLEGAL and Unpatriotic – if you want to live in a theocracy – there are many nations that use that form of government – you only have to move and change your religion.