You are equivocating. Blindness as a personal chronic medical condition is not the same as a situational difficulty.

The pilot who is "flying blind" has perfectly normal eyeballs. They are not necessarily a member of any minority group, except for their chosen profession.

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As for "blind" being a word that appears more frequently in a negative rather than positive way... Well, I'm not sure what to tell you, that's just 10,000+ years of language from a species that evolved to prefer seeing.

To offer an example of the positive case, the idiom "justice is blind". Yes, there is a popular cultural mascot wearing a strip a fabric over her eyes, but again: The justice doesn't actually involve any (real) personal medical condition, and it's considered a positive feature for the job.