I agree with the use of disabilities like blindness and deafness as metaphors for something negative is a hurtful practice.

On the other hand, for words that have a very archaic meaning to refer to someone's condition (that subsequently is replaced with a different definition in common usage), I think it is best if people let go of such old definitions. People should not allow themselves to consider such usage as a slight upon them, unless such phrase was used specifically as a slur against that person.

And that goes for any kind of word. For example, if I use the terms master/slave in a discussion about computer hardware, it's clear I'm not talking about any enslaved population. To make a fuss about that, to me, is people making things their problem and quite silly.