Though they know God's righteous decree that those who practice such things deserve to die, they not only do them but give approval to those who practice them.
Romans 1:32 ESV

Everyone instinctively knows that heterosexuality and marriage are natural. They have to convince themselves otherwise through choice and practice, or else by pain and brainwashing inflicted on them.

Since we were created by God for God's purposes, those who reject what they know to be true and reject God's plan for them have no reason to complain about their condemnation. They are useless tools, so why should the toolmaker allow them to take up space in his workshop?