RenkonNairu is the Emperor's Foot

I think people forget that context and tone are key to storytelling. Like if She-Ra did take it's war elements seriously and show Catra and Hordak burning villages, taking mass prisoners and using slave labor in the Horde, it would have been SUPER HARD to accept both characters having "Happy endings" because people would be like "What about the slave camps".

Hence why they didn't show that stuff and made the Etheria War more like a school clique war. Because you want to be believable enough for Catra and Hordak to have happy endings at the end.

That's why they gave Horde Prime most of the horrible atrocities both on and off screen since he wasn't getting redeemed and he was the ultimate evil. So they could go full blast with showing Prime geocoding worlds and what not.

Tonal context is key to any type of story i think and She-Ra's both light hearted nature mixed with scary moments is key to the success. Or any successful series really.

SPOP did take the war seriously - in season five that is.

We see refugee camps, we see people being displaced, terrorized, controlled and even harmed in Horde Prime’s effort to gain control of Etheria.

We see Horde Prime committing genocide on a planetary scale,

and we see the outcome of his conquests both in the form of destroyed worlds, extinct peoples and subjugated ones and in the relics he kept of them

Season five did not shy away from any of that. The tone was as dire as the situations the characters found themselves in.

There were no more Princess proms or organizing parties with moth people.

The strategizing that goes on is taken seriously and not treated like a D&D game.

Even characters that had a small role such as Bow’s dads - characters who during the war with the Etherian Horde in the first four seasons enjoyed the luxury of living and their lavish home away from it all - these characters are now on the run for their lives.

Whereas the first season implied that everyone has lost someone to the war we don’t really see any of it. Worse still the only confirmed casualty, King Micah - turns out to have not been a casualty at all when he is found alive on beast Island along with Entrapta.

If the series had wanted Hordak's war to be serious, it really could have done it by showing us the things it did in S5.

We are told at certain points that people have ‘lost someone to the war’ but we are never actually shown anyone grieving for their loss.

A lot of fans claim that Hordak was responsible for the death of Mermista and Frosta’s parents but that is neither mentioned in the show nor used as a reason for them to join the rebel alliance. Mermista’s dad ‘went away’ for some reason just like most of her people, people that had been leaving Salineas because she refused to do anything about the fact that the Sea Gate was failing back in season one. Adora fixes that problem for her which lead to her deciding to ally herself with Glimmer's war effort.

We do see plenty of property damage especially when season four comes around and Catra’s amplifies the war but not much beyond that.

It is implied that upon Salinas’s assault, everyone got away scot free. And yes, I acknowledge that having their homes destroyed is terrible in and of itself but the scene doesn’t have the same tone that the whole of season five did. It is not explored what happened to these people after they were turned refugees nor what the loss of their village meant for them. They are briefly forgotten by the show, their struggles are left unaddressed.

The general terror of the people in Earlandia come season five however is clear. These people are just as fearful of Horde Prime as they are of their own princesses. They live under terror and martial law with robotic drones and clones patrolling the streets.

It would’ve helped to set a darker tone if the refugees from Salineas had been even a footnote somewhere beyond the episode where the Sea Gate fell. We do not see refugee camps, we don’t deal with any of the logistics that come to mind when dealing with massive locations of people or the resource shortages. They are merely forgotten by the narrative.

Mermista copes with this loss by moping and eating ice cream in a bathtub.

She doesn’t go to rescue her own people. She is never shown trying to take care of them now that they have been displaced as would have been fitting for a ruler. That issue was never addressed.

The only person shown grieving in the first seasons is Glimmer. At first for her father, and after Catra’s activated the portable device before it was ready, for her mother. This loss is what made Glimmer do the things she thought were necessary and sadly, that is completely forgotten in season five when she doesn’t mention her mother once nor does she get a proper reunion with her father whom she had believed dead for so long.

We do see refugee camps and people on the run in season five. The urgency and bleakness of the situation is underlined over and over again. We are no longer shown people living comfortable family lives while the war was happening somewhere else.

Even Peekablue’s soirée had an air of desperation to it, that of people trying to drown their sorrows and the run from the oncoming apocalypse.

The concept of “losing someone to the war” becomes reality for a lot of the characters as their loved ones become chipped and turned against them.

It’s not that SPOP didn’t know how to set a grim tone for the war. It did, with Prime’s war.

Your assessment of the tone for the first seasons being that of a “school clique” is apt as well as the reason behind it.

The show had always intended to redeem Catra’s and forgive Hordak. Having them commit actual atrocities on screen would’ve made it unpalatable and tone deaf. (Though that doesn’t stop some fans from imagining Hordak’s supposed crimes and even headcannoning some of them like claiming that he was responsible for murdering Catra’s people - which was something that was never mentioned in the show but people love bringing it up anyway)

The first part of the war had never been meant to be taken seriously whereas Prime’s conquest was.

It’s strange that so many people insist on comparing the tone of the first seasons with that of Avatar the Last Air Bender when that show had always maintained the grim atmosphere of a world at war. People always mentioned how strange it was to see an air bender in the flesh since they were all believed dead. We see broken families on both sides of the war and we see resource shortages, rampant crime and violent battles.

Does anyone ever mentioned Scorpia’s people in the show or how are it is to see a living Scorpioni if they had all been genocided? They don’t because the genocide was never confirmed verbally.

The only scene that would imply something had happened to them were visions shown to the Council by Light Spinner - a proficient illusionist with clear aspirations for more power.

It’s peculiarly funny to me how so many people insist on treating the first four - more lighthearted - seasons of the show as if it were serious war drama the likes of Saving Pvt. Ryan.