If this is the reason to why everybody was upset over the finale, then I completely understand. But its no reason to send death threats.
 
Fortunately in my headcanon, Twilight released the villain trio after some time has passed and offered to help them find peace. The process surely wasn’t easy and they had to take extra measures to ensure the villains were still being punished. But eventually, they found a middle ground they could all agree on with the heroes and could finally put their hatred and arrogance behind them. Chrysalis did transform into one of those “glitterbugs” everybody hates so much but is usually seen in her old appearance.

@AC97  
She might. If she’s a narcissistic sociopath, the absence of others would disturb her. No one to give her attention.

@royalbardofequestria93  
Exactly.
 
@Mr grump  
Why would celestia have authority over another empire? And he became leader long before Cadance was born.

@Mr grump  
He could have inherited the position and went nuts.

@PonyPon  
Not in equestrian society it ain’t.
 
And sombra not illigitimate? I must have missed the part where he was appointed by celestia or defeated cadence in a democratic vote. I could have sworn he used enslavement and dark magic to enforce his rule, not a mandate from the people.
 
I’m unusually snappy tonight. I’m going to bed.

@Mr grump  
Pertification and imprisonment(or as least one person has suggested, mutilation) are way above ‘societal’ consequences.
 
And, no one ever said Sombra was illegitimate.

@Wild Stallions  
The British executed children, but they were and are ruled by an elite of Norman psychopaths.
 
#FreeEngland.

@PonyPon
 
Fearing the just societal consequences of committing murder and theft is the same as fearing the consequences of disobeying the illigitmate dictator who usurped your home and brainwashes your friends for his army.
 
Gotcha.

@Starswirl  
Even if that were true, it would still be righteous and deserved if the crime were abhorrent enough. If there were no consequences for breaking the law, the law may as well not exist. But even without the law, fear of punishment would still act as a deterrent because you or I would defend ourselves and whats ours, violently, if necessary, law or no law.
 
Anyway, these three ain’t dead and probably not even conscious, unfortunately.

@Mr grump  
Trying to control others through fear, isn’t that why we killed sombra the first time?

@Mr grump  
As far as I am aware, fear of capital punishment does next to nothing to deter murder.

@FearDiamond  
I disagree. Repeat offenders who pose a threat to innocents and their homes and livliehoods need to experience the suffering they inflict on others, whether by imprisonment or harsher methods. The unlikely rehabilitation of such people should be a secondary concern and only attempted once punishment has been meted out and victims have received justice and retribution.
 
Fear of punishment has always been the greatest deterrent.

@FearDiamond  
If they are sent to Tartarus it will only hurt them more. Being alone will not reform them. They need to observe ponies for a while and then get reformed like Discord in S3

@Starswirl  
I’m content with what I got this episode. If it were up to me, Discord and Starlight would have been dealt with in a similar manner a long time ago.

@Mr grump  
Wow, you’re one tough son of a bitch, aren’t you!

@Background Pony #94E0
 
Tell me, why do they need to “pay” with petrification, instead of by being sent back to Tartarus (though even this was itself borderline unacceptable for Cozy)? Tirek only escaped the first time because Cerberus abandoned his post, and neither he nor Cozy seemed to be attempting or even considering an escape before Discord freed them. It was effective and did exactly what imprisonment was meant to do without risking destroying their psyches forever. Why go beyond it unnecessarily?

@Mr grump
 
The point of punishment, in this world or any fictional one, is not and should not be the cruelty.  
If a punishment is more cruel than it is potentially useful, and this certainly is, it is immoral.  
We don’t imprison murderers so that they will suffer. We do it so that society is protected,  
and at least ideally (although little effort is made by the system in practice) so that they can be reformed.  
Reformation is one of the key focuses that justice, and criminal justice especially, is built on.

@Mr grump  
Like Discord? The ponies were incredibly lenient with that one even after he openly stabbed them in the back.

@FearDiamond  
Good. Horrible people and villains should suffer. If their sanity remains intact, they’ll certainly be to terrified of reliving their punishment to reoffend.

@FearDiamond  
Im sure they will prepare Keep Calm and Flutter On scenario for them when they cool off. They still need to pay for what they did, causing a war and destroying Canterlot castle. Im sure Discord will have to also be punished so he will be responsible in reforming them.

@AC97
 
But if they are unconscious, then the punishment is meaningless and we are back to square one. Why do it at all?  
They aren’t going to learn sh*t from being petrified if it basically lasts the blink of an eye in their mind.

@Mr grump
 
If they are aware and stone for any meaningful period of time, they won’t contemplate anything.  
They, especially Cozy, since she isn’t a monster and therefore would experience time normally,  
will just simply go insane. Imagine if you were trapped somewhere, literally unable to move, speak, or otherwise interact with the world but totally conscious of the things going on around you and the passage of time, for years.
 
You would lose your mind. It is solitary confinement turned up to eleven, and is completely barbaric.  
Either they aren’t aware and the punishment serves zero purpose, or they are, and you condemn them to insanity.

@Mr grump  
Even if they are aware, its still better than being aware and inside a tight cage in tartarus. I think Discord convinced sisters to turn them into stone instead Tartarus, because now Discord can attempt to reform them with Fluttershy or someone other whome Discord find worthy enough. Celestia and Luna would just throe them into tartarus and i think Tirek woudn’t handle that for long.

I hope they’re conscious and aware so they can contemplate their mistakes and misdeeds.

I don’t think villains are aware of being stoned. Discord was made out of Chaos so his body trapped in stone was like a gas trapped in a balloon. He was aware of everything because he doesn’t have organs that would turn to stone. Every other organic creature would have their brains turn to stone which mean they wouldn’t be able to process reality and be aware.