Studies have shown that making more money does not make people any happier. Job satisfaction is far more important.
One person's "excuse" is another person's reason. This is simply semantics. He is trying to put you on the defensive for not doing what he wants you to do.
When you say he says your reasons are "just an excuse," that implies you are arguing about it. There should be NO argument about you doing what you like to do instead of learning a job skill you find difficult and unappealing. This is simply your decision; he should not even be arguing with you about it, let alone calling your personal choices "an excuse."
Try this: Tell him you've been thinking about this and have decided to stay with your present job and career. Then sit calmly as he rants and mentally give him a time limit (like 2-3 minutes) as you listen with no response or argument. Then say, "I can see how strongly you feel about this. Nevertheless, that is my decision." And do not have any argument about it. You can say, "This subject is closed for further discussion." Then change the subject to something pleasant.
