I'm building the automation that replaces jobs like mine. Is that wrong?

You built something that works. It does the job faster than the people who used to do it, and now you feel sick about that. You're calling this guilt. Look closer — it is not guilt. It is confusion about which kind of person you are. You want someone to tell you whether 'useful' and 'good' are the same word here, so you can stop carrying both possibilities at once. No one can hand you that answer, because it isn't a fact sitting out in the world. It's a judgment you make with each choice you make next. So stop asking the big question. You did not invent the forces that reward speed over people. You cannot undo the tools already built. What you control is narrower and closer: what you build next, how you build it, and what you say when someone asks you to cut a corner that costs a person their work. Start there.