Golonya
Mugetsu Ookamiza
I've been watching anime since the first half of the 80's. the only difference right now is I tend more to watch stuff aimed at the older half of the shonen and shojo demographics and seinen. they make anime aimed towards more than one age group, including adults. not to mention, my mom watches it with me. seriously, she's 68 at actually likes some anime.
and to quote C.S. Lewis:
"To be concerned about being grown up, to admire the grown up because it is grown up, to blush at the suspicion of being childish; these things are the marks of childhood and adolescence. And in childhood and adolescence they are, in moderation, healthy symptoms. Young things ought to want to grow. But to carry on into middle life or even into early manhood this concern about being adult is a mark of really arrested development. When I was ten, I read fairy tales in secret and would have been ashamed if I had been found doing so. Now that I am fifty I read them openly.
When I became a man I put away childish things, including the fear of childishness and the desire to be very grown up."
there is no reason to be concerned about watching things that may be considered "childish" if you really enjoy them. we needn't be concerned with labels and should be secure in who we are and our own maturity. the whole "how old is too old to watch anime/read manga" strikes me as people being too concerned about looking childish or trying to make people feel ashamed they're interested in something "childish." it's completely needless. it's entertainment, nothing more, nothing less. it shouldn't matter how mature or immature it is if it's something you like regardless of what age you are.
I was genuinely hoping someone would go to that Lewis quote. I was making a wager with myself over when to expect it. I can't state that I disagree with you fundamentally, Poster, but that point of view is sadly not commonly shared in the society in which I live. I was hoping that, in asking people what ages if any of people enjoying their fandoms or even related fandoms, I could spark a discussion and forward a similar philosophy. Trust me--you're preaching to the choir, even if there haven't been a lot of series that speak to me personally of late.
As to reasons for being concerned: Do you think employees of, say, government run contractors would be comfortable watching anime on their lunch break? How about reading manga on the train? It's all well and good to make the claim that we ideally should simply enjoy the things we like regardless of who might be judging us for them, but sometimes we represent things--companies, for instance, or institutions--greater than ourselves. I'll grant you, more often than not it'd be inappropriate to enjoy manga while that is true; but there are elements or reputation that many people tend to give more consideration to than they are willing to admit.
There is a time and place for everything. Just like a lot of workplaces have a dress code/uniforms and deem some outfits as inappropriate, but doesn't mean you can't wear them outside of work.
Being professional and representing companies doesn't mean you can't enjoy anime or manga, but to put your work first (many would probably frown upon workers watching soaps or talk shows as well while you're at work, even during breaks).