Teach me, please... What is immoral if you open your Limited company and sell your programming services to some customers and make profit doing it?

Make it economically bad times, and the customer a shady actor. Will the company deliberately close and stop offering its services, despite needing to put food on the table? Or will the company just go along and do the coding for shady customer?

Now, put a lot of air in that thought-baloon and you will see how basically every for-profit will end up doing immoral things.

You are wrong! Not every for-profit will end up doing immoral things in this case! Some will move on to do other stuff...

Most people in the developed world are all immoral according this argument.

https://www.youtube.com/watch?v=cTsfzLTBuo0