I echo the sentiment that not a lot of people can handle the commission process at that stage in their life. The fact that you had done commissions since earlier on gave you a foot up. Your personal experience was significantly different from many of your peers.
I think it's this experience that makes a big difference.
Also, remember too, that everyone has walked a different path in life, have had different experiences, and thus their "filter" of "how to do things" and "what to do versus what not to do" is based on this. All said, this is true for everything in life.
I don't like blanket statements, as it utterly ignores the outliers, the random bits of life that do not fit into any box.
That said, my sentiments come from my own college experience. In, of all things, an Art History class, a teacher had us do a poster project. He wasn't grading us on the art, per say - but the process. 1 out of about 20 students in the class got the "A", and that art piece violated certain rules he had in regards to the project (like no printed out font, it had to be drawn). The piece was no where NEAR the quality of the others.
The best individual piece in the class, got a D.
There is a fine line between bowing to a client's whims, and doing what you know in your heart works best. It's a dance. Not a lot of people understand this dance, and either ego or fear ruins it. Most college artists don't have that experience, that insight, or that understanding. Those who do side commissions (like fan art work, or convention table work) will learn it eventually (or maybe not). Everyone is different.
That's what he was testing us on, our ability to interact with a client. 1 out of 20, in ONE Art History class Mixed bag class of various majors, mixed genders, mixed backgrounds. He told me later that he only had two people get A's in the four Art History classes he taught that quarter, and he'd only had a handful in the last two years. Think about those statistics.
My personal advice in regards to such things as taking freelance work is simple: If you know how to do it, and it's not too much on your plate, do it. If you have to choose, weight your options carefully base don your priorities.
I had two fellow classmates who quit school as a freelance gig turned professional-long-term on them. shrugs One eventually came back and finished their degree, the other kept going with the company that hired them.