So you think that those who suffered this, who you earlier wanted to complete, and want to see the prosecutions are just thinking about vengeance and their opinion should be taken after your's because it's not important in your view.
If the law has been broken, then people need to face the consequences, but your attitude stinks.
It's much more important to ensure that things like this do not happen again and much more important to fix the system that let this happen.
Again, if there is no accountability, then the lessons won't be learned.
Let's say Paula Vennells goes to prison. Who learns a lesson from that and what lesson do they learn? Paula Vennells learns that she shouldn't have done what she did but she is never going to be CEO of a large organisation again and it would have been better for her to learn the lesson before she took over the Post Office, so the lesson is wasted on her.
Will other people learn lessons from her conviction? Maybe, but the lesson might be "if you screw up, don't get caught".
The reason I say your attitude stinks is that my position is quite nuanced but you are trying to paint a black and white picture so you can score your debating points. The reality is that the desire to make people pay for the damage they caused and the desire to find out what went wrong and fix it for the future are in tension and it's a tricky path to navigate.