I'm not quite sure why this one has such a poor rating. That is, unless the response is that shows that are clearly intended for children are rated according to criteria meant for an older audience.
It's performing fairly well, judging by the criteria for a children's show. It's not as badly written as kiddie cartoons usually are, and despite a few corny scenes, it's good enough to pass the time as an adult if you're looking for something simple to watch in the background while you multitask. Which, if it were stupid, I couldn't accomplish.
The program, which is intended for American and Japanese audiences, has unexpected moments, especially when the main characters are led to believe they are heroes. The show highlights the difficulties of adjusting to a reversed world by making references to "unspeakable things" and the conflicts of the protagonists.
The terrible "character sacrifices themselves for a dramatic moment as the others lament the demise, only for said character to turn out just fine mere seconds later, completely nullifying previous emotional moment" is one of the many clichés used in Future Avengers. To be honest, I'd be shocked if anyone genuinely believed the key characters would die.