Not that I agree with the practice but the people pro death are also pro retribution; to them the suffering is a feature :/
Otherwise you're just throwing shade on people you disagree with, and that doesn't make you look good.
> I have not met a single human being who believes in execution but only humanely. I have met in excess of 50 people who simply conflate suffering and death and simplify the justification
The very best this statement can say is that inside your bubble, this is how your memory represents the aggregate opinions you've encountered w.r.t. the death penalty.
I can't remember the documentary title, but the example was given of humane, even pleasurable, similar method to use instead of injection etc and it was dismissed angrily by pro campaigners for those honest and believable reasons.
That's not to say it's a majority opinion - so I agree with your objection to that generalisation, but it's definitely a reaction of some who are pro-death penalty.
It seems fairly common these days to throw shade on people we disagree with, and it bothers me.