Well isn't that nice you live here all your life, take up fishing in your retirement, and now you want to learn more about the fish than just how to catch them. Beware as this is the first step to enlightenment. It starts with a simple question and is followed by a complex and troubling answer that leads to more questions and greater investigations and pretty soon your fat ass won't have time to be watching TV you will be outside doing stream rehab and volunteer work on redd counts!
Far better to remain ignorant and to continue to harvest what you want when they let you and never pay any attention to the riparian uphevals that have been ongoing as you have lived and worked here on the OP.
Seriously hatchery fish are a real challenge to explain in many ways it pays to just look at how poorly the retuns to hatchery's have been over the long haul and you can answer your own question the fish from hachery spawn are not as successful as wild spawned fish. So it stands to reason that if you spawn a hatchery fish with a wild fish the progeny will be weaker than the wild wild spawned.
There ain't a hell of alot of releigion in the need for minimizing our harvest of wild fish and a "full blown catch as many as it takes too make you feel good C&R season " is as repugnet to me as the bonk em all before the other guy does mentality. I have been borned raised and fished on the OP since 1948 and have been realising steelhead and trout since the late 50's. To me it seemed like a good thing at the time and it still seems like a good idea. I am always a little suprised at how negatively the simple gesture of release can generate so much opposition. As a lad when obseved by elders in the act of release I was many times criticized as being wasteful and worst, but It was obvious then that the main complaint was about there greed to have what I had and let go. But I digress< take the time to read Salmon Without Rivers by Jim Lichatowich and if your TV runs out of electricity go to the library and checkout Haig Brown Return To The River.
As to fishing fulltime, congratulations best advice I can give you is buy some Breathable waders.