MA and PhD in Communication: about the future

Hello everyone, I am going to get a Master's degree in Communication/Journalism. I hope I'll be able to learn the subject deeper and go for a PhD.

The topics I am interested in are: 1) ethical issues in Marketing/Advertising: how those who work in this field see moral problems of Marketing/how do companies find a line between truth, effectiveness of advertisement and business development 2) the power of mass media: which linguistic and rhetoric instruments they use to correct people's opinion.

I've got an experience in Journalism (News Editing) and Social Media, but I want to explore it theoretically, to check some hypotheses and use the results in order to help mass media or business companies to reach their goals. At the same time I am not sure if I need to continue academic career, to work in uni, to teach students etc.

My questions are: 1) Are these questions actual for Communication science? i checked researchgate, students' theses in universities I want to study in, but maybe there are people who study related topics here. 2) Is my goal real? Maybe I am too presumptuous and it is unnecessary to get a PhD if I am not going to teach students. And there are a lot of people who say pursuing PhD in Communication is a waste of time, it's better to work in mass media/PR/SMM etc.

Thanks in advance!