of course they are trying to prevent mistakes. The anti-relationship law wasn't just to screw over the Star Sapphires. It's something all types of militaries all over the world. It was because GLs in relationships with children were being targeted for murder and focusing on their families. And there was no punishment meted out to those who quite.
I also think the Guardians handled themselves awesomely against the Anti-Monitor and Superboy Prime.
They're not coming off great here, but they're not total monsters in my opinion.