Things have changed drastically, as equipment became more effortable to the mass, so many people can call themselves engineers and composers and whatever. However, one thing remains: You can have the greatest gear at your fingertips and the best sounding studio/room, but you can’t learn that craft in a year or two or three…and this is where most people stop. You can ask someone to do a mix for you for 50$, and most likely you will get that qualify for 50$ as well. Experienced engineers are paid for their experience and their taste. And good taste comes ONLY throughout many many many years in making music and learning the craft in and out.
Can anyone insert a compressor? Yes.
But can anyone tell you why he used this compressor? No.
On the other side, I heard crappy work from multi-million dollars studios throughout as well. Equipment never will do the work for you, only knowledge, experience and taste, as I said before, and this should cost more then 50$ a mix.