If you have a crappy attitude I can't do anything to help you there.
If you have the aptitude and your attitude is positive, can-do, willing to learn, we can teach you anything you need to know or you can learn it on the job.
I too worry that "Cultural Fit" is becoming the new "don't like them" excuse of the day. I try hard to hire people who think about problems differently than myself or other members of my team. My hope is to get as many angles as possible to see problems from so we together as a team can find solutions that might not have been obvious if each of us has a homogeneous view driven by some bogus "cultural fit".
What I know about my life is I was born with almost none of the skills I leverage every day. From the ability to walk and talk, I've had to learn it all. I feel focusing too much on fit and skills is like judging a baby on how cute it is. Basically useless.