'Yes, the word, "pro" is as meaningless today as the "all natural" on a food label. I consider someone who makes their living doing something to be a "professional" because it is their "profession". It is their trade, their job. I am a music teacher full-time, and a part-time engineer/producer. I built and own a recording studio that 4 other engineers work out of. But we are all part-time. We all have other gigs that pay the bulk of our bills. By my own definition, I'm not a pro. But since I rarely set foot in the studio without being paid, I do consider myself a "pro".
One thing is clear, just because someone IS a paid professional, it does not necessarily mean that they are more skilled or knowledgeable than someone who is not. While it tends to be true, it is highly circumstantial.
Lastly, no one on these forums looking for help (as I have done many times) has the right to wave it anyone's face or use it as an argument. There is always a respectful, logical way to explain why a particular suggestion isn't helpful.