There are a large number of wannabee techs everywhere including here. Not trying discredit them but a lot of things posted are based on a guessing game and hold little factual value. I've seen this many times. That's ok, it keeps discussion going but can sometimes derail getting accurate info.
Having said that, yes, there are many very good, knowledgeable techs here on the forum, such as Chris Bryant and others. Every post I have read from Chris has always been accurate and factual.
Then there are many other non techs, who have many years and decades of hands on experience at virtually every aspect of RV service and repair. By this they become an expert in their knowledge, skill and ability, but hold no formal education or training in this subject. Some people just naturally have been blessed with an ability to put their hands on things and fix them.
I don't claim to be a tech or an expert on RV's, but after working at a trailer factory in the 70's, and repairing RV's for 40 plus years, I've gleaned a little skill at it. Sometimes, an aptitude and ability coupled with years of experience can be much more useful than a couple years worth of education and a piece of paper that says you're qualified to fix stuff.