I do agree he made a mistake But I actually liked the Finale For a couple of reasons
It showed that Inahos way of thinking Is not perfect and that he has a flaw, Which is that he is too “Logical” and which is what Killed him in the end, If he Didn’t shoot down Slaines plane he wouldn’t have died, While it was the logical thing to do it still was a big mistake
It makes for a good cliffhanger, With Inaho dead and The fact that there are a lot of martian knights still wanting to attack earth it makes us wonder what will happen next, and What will happen to Slaine, both sides want him dead so what will he do next? and Why was the princesses body stated messing
So overal I Enjoyed the ending even if the show itself had a lot of negatives.
On another topic I hate how they ruined the Terraformars anime with censorship