your lizard brain is eventually going to associate car theft with dying
That's not car thieves dying while stealing a car. The connection between the state executioner killing someone and car theft has several conditional layers between them. Remember: What if the car thief hadn't eaten breakfast?
The criminal's answer to the long chain of events of do crime, get caught, get charged, get prosecuted, get convicted, get sentenced, get executed, when you point out those those criminals being executed on television? "I won't get caught." What if you do get caught? "But I just told you I won't get caught." In the unlikely event that you're able to get them to understand the hypothetical conditional where they do get caught... "I won't get charged."
That is what "maximum deterrents" are up against.
And that's not even bringing up "Police be racist and shit.", where you point to the convicted criminals being executed on television and that has nothing to do with the consequences of stealing a car, because those are innocent proud black men being murdered by whitey.
punishment needs to come back as a replacement for extremely long prison sentences (which don't seem to rehabilitate anyone anyway).
EVEN IF deterrence, punishment, or rehabilitation
DID work, telling the government it is justified to harm you in order to deter, punish, or rehabilitate are sufficiently horrifying paths to go down that it's not worth the risk of even considering such claims reasonable.
Stick to separative justice. In which case, "extremely long prison sentences" are extremely effective in stopping the imprisoned criminal from committing further crimes against free society for the extremely long duration of their extremely long prison sentence.