To everyone complaining that they could have talked through their problems and “misunderstanding”: they never would have. Sophia isn’t really on side of the demons against the goddess, they are just allies of convenience. Even if they really believed Makoto (which they had literally every reason not to) his existence is too absurd for them and would have been a threat either way to their real ambitions. It’s not shown well here in the manga but they understood his dangerous potential and wanted to erase him, full stop, goddess or no goddess. They were destined to be enemies. I could go on but that’d be spoiling too much, just read the LN translations.