If one were to base his/her observation on what is posted on this board then I might be inclined to agree with this. That, however, raises the question: Is HBT truly representative of the American homebrewing community?
I'm not sure that it is. I'm an old guy (a 51 model). I have, however, had a presence on the Interwebs since the early 90s when this remote, rural backwater where my farm is located first got access to the Internet (if you can call 28K dialup "access"; it's gotten a lot faster since then). I have observed, from participating in a number of message boards, that the majority of message board users are not representative of the typical individual who is involved in the <insert hobby/special interest here>. There are a lot of people who are involved in a particular activity who have no interest in any of the online resources which are related to that activity. I base this observation on 25+ years of participation in message boards related to aviation, agriculture, woodworking/carpentry, shooting sports, homebrewing, and probably a couple of other things I can't think of right now. So, all of that said, I would say no, the horizons for homebrewing are not narrowing. This board might give that impression, but I would be willing to bet that the average homebrewer in the US is not cut from the same cloth as the HBT members who are all about the latest Big Thing.
I've drawn essentially the same conclusion. The people on these boards are not representative of the homebrewing world--they're much more into it.
I'm a member of a homebrew group; when I first joined, I had hopes I'd be able to learn about homebrewing and accelerate my learning curve. Nope. Oh, there are a couple of people there who I'd consider advanced, but mostly not. Most are content with where they are in homebrewing, mostly doing extract kits, mostly doing what the LHBS has put together for them to use.
And the internet? Agreed, not a resource for most of these people, maybe 90 percent. The internet is what I turned to early in my brewing career, and THAT is what accelerated the learning curve.
BTW, IMO people get to do what makes them happy, and I'm not putting in a dig at them. They get to choose, not me choose for them. And vice versa.
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Why don't people take advantage of what's sitting right there in front of them, free for the taking? It depends on your nature as to whether you want to plumb the depths of a hobby or subject, or are content to just be where you are.
I suspect, also, there's a certain willingness to accept the occasional failure, I suppose, in trying the new and weird things. Anybody who watched my homemade glycol chiller odyssey knows how many times I failed as I tried to find a way to make it work. Each failure was a step closer to the solution. Each mistake was a process failure, not a personal failure.
And in fairness...some of what I'm trying is dependent upon having resources. I'm an empty-nester. If I'd been interested in this 15 years ago...no way could I have afforded it.
But there are ways to improve that won't break the bank. The key is to want to improve.
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I've been pondering this--you have your string of hobbies over the years, and I was laughing at it, as I have my own. I was thinking about how "typical" a user of various boards is, and like you, concluded that they're not.
It can seem to me as if "everybody" is doing something, but that's only if I focus only on the echo chamber here. The people on HBT tend to think similarly, and their views tend to coalesce over time as new ideas become established.
So I have a tendency to think, because I'm a sponge for information on and off the internet, everybody is as tuned in as I am. Nope. Not even close.
I do shooting sports, and reload my own ammunition. I've gotten to the point where I cast my own bullets out of lead alloy, and even learned how to powdercoat those bullets instead of using standard bullet lube. I thought it was common knowledge about doing this. Nope again. It just SEEMED like everyone knew about it, because I was a frequent member/poster of a bullet casting forum. I know of nobody within a 100-mile radius who also does this. I've talked with people at shooting events about it--there's nobody to share info with!
So, yeah, we're weird here. Thank goodness.