The thing about using slurs is when you respond with "but [group] deserved it!" you've implied that you're happy to use it against someone if you subjectively believe they're "deserving" and that the term should be received negatively
Both terms obviously should be received negatively, they are insults. That's how insults work.
I am happy to refer to more groups, not only Tesla investors, as retards too. I'll leave this as an exercise to imagination.
Maybe you are running out of things to feel sorry about.
Either way, this conversation has run its course. Have a wonderful rest of your day.