I have handicapped myself by learning something that wasn't practical at the expense of something else that was.
What one is not going to hear much in this thread are the opinions of folks on the higher end of the autism spectrum, who carry for self defense so they can go home at the end of the day and spend time with their families and/or people they love. Because they are too busy doing that. They assess their threat environment, choose a means of protection, train adequately to that perceived threat, and go on with their lives.
In the case of the J-frame, that involves a cost/benefit analysis of factors including availability, expense, training time, ammunition cost, accuracy, magazine capacity, concealability, etc… And all those criteria get muddled in with concerns about job, traffic, income, child rearing and all life's myriad issues. Each person has to make their own assessment of their threat environment, and act accordingly. The J-frame is often not going to mesh well with these criteria. And this is not a failing of the shooter. The shooter has other things on her mind, because the shooter leads a rich, full life, and has to balance a number of concerns. The problem is with the J-frame, because it demands more than many shooters wish, or are able, to give it. And this boils down to the design of the firearm.
It's easy to blame the shooter for not being able to 'hit a basketball' at 100 meters with a J-frame (or whatever). And that's probably what's so attractive about it- just sitting there in your mom's basement, rocking back and forth, blaming that shooter.
And that said, the demands of the J-frame, for some, are probably a net positive- one has a surfeit of free time, a healthy disposable income, and could probably use a little time logged out of the internet forum and in the company of real people, so one can learn the finer points of social interaction, such as having a conversation without needlessly picking apart every niggling detail of the statements of one's interlocutor, and realizing that we're all human, and fallible, and that one's skill at shooting the j-frame, or factoring primes, or whatever forms the center of one's emotional universe at the moment, isn't necessarily all that.
And I say all this as someone who carries a Model 36 daily, and frequently surprises himself by ringing the gong at 100m with it. Is that a goal I train toward? It certainly is not. I train toward the threats my experience and reason have taught me to anticipate, but only to a degree that it doesn't detract from the life I intend to protect by going armed.