Dizmox, I'm curious if you meant that non-business types your own age are less likely to be fluent or less likely to be arrogant?
In my experience, most (older) business/academic/govt types who use Japanese in their work aren't particularly invested in their identity as "fluent Japanese speakers" and don't feel compelled to show off or lord it over others. If anything, they identify with their work and Japanese is just a means to accomplish those goals.
They're not likely to post youtube videos of themselves speaking, spend time on Japanese related forums seeking recognition or admiration, or engage in "fluency" competitions. They're not trying to sell their 'exceptional' results (and, in doing so, unjustifiably dissuading people from alternative approaches.)
I think it's similar to the many multilingual folks here who don't really see their linguistic skills as a big deal. Or people who marry into and raise families in a foreign language environment. It's hard for me to imagine them saying "Hey, look at me! I can talk to my kids and neighbours!"
I also think that trying to use Japanese for life and work has a humbling effect. Even after several years, many people recognize that they're not going to be 'native-like': there's always more 'unknowns' and room for fine-tuning the 'knowns'. There are awkward moments. And they don't want to be self-conscious about people assessing their Japanese skills when they're trying to focus on the job at hand. So perhaps that creates more mutual support ("I feel your pain") rather then one-upmanship?
Not sure how much that's a function of age, though. It seems more related to attitude/purpose/personality.
It's a matter of degree too, isn't it. A little friendly competition can be fun and motivating. Most people admire the commitment it takes to learn a foreign language. The excitement of being able to use a new language is only natural.
The internet has certainly helped make language learning an accessible goal for more people. But ... I can't help but feel it has also created these social pockets centered around language learning stars or extremists, rather than the language itself. Educational community building is fantastic, but sometimes the quality of information suffers a bit and the dialogue veers away from the ultimate goal. Ideally, accessibility and quality will move in tandem.
Oops, didn't mean to write an essay... :-) [Edit: I also didn't realize I was repeating some things mentioned earlier in the thread.]
@OP: As for someone who tells you your Japanese sounds "retarded"? I'd make a mental note not to take anything they say seriously. Hopefully they're a more decent person IRL.
Edited: 2013-03-21, 3:18 pm