I have been a copywriter for 30 years. I  cut my teeth in the agency world, including CPB+. I was the associate creative director for a public company. I've been there, done that, MadMen-style. Technology has changed the channels we use to communicate, consume information and entertainment, and make purchases, but it has not changed who we are as a species. Consumer psychology still operates according to fundamental conscious and unconscious needs.

I write conversion and SEO copy, long-form sales emails, and app microcopy. I don't write blogs or social media posts, although I could if you put a gun to my head.
I understand UX fundamentals and how to map out content in a Balsamiq wireframe. I'm no developer, but I built this site without a template (I used WordPress, Oxygen and CSS). 

Most writers can do basic research. I am formally trained in research methodology. At one point, I did ethnographic research among tribal populations in Alaska for the Bureau of Indian Affairs. Suffice it to say I love research and am good at it. I use it as a foundation and a reality check for the development of creative work.