While I admit that I had difficulties with this particular gun, you're just being much of an arse based off one example. One.
There are no qualifications to be a tech; if you're good enough to be one, you can just be one right off the bat. And, a professional is someone that has an income based off what they do. These are the facts and that's just how it is whether you like that or not.
My reputation is currently local and through word of mouth. I have fixed and passed on quite a few guns with no complaints so far. Yes, this G&G may end my positive streak, but are techs not allowed to make mistakes and learn from them?
I've made around £1300 so far this month. No, that's not a huge six figure "pro" salary. But, I think that's pretty decent for an engineering student on summer break with a lot of spare time. Enough for rent...