If anyone told me that they are good at everything, it would show a lack of self awareness if they have only been working for three three or four years and would be an immediate red flag.

But your real issue is that you have a generic experience that really doesn’t stand out and the software development field is saturated. Yes I know everyone has to start somewhere. The market just really sucks right now and there really isn’t any reason for companies to hire junior developers when they can find their perfect match.