what is the consensus on whether we should avoid using "blind" as a category of persons

I am not an expert on this topic, but a look at this page suggests that “blind” and “the blind” is how blind people in the United States most commonly refer to themselves, at least in the names of their associations and advocacy organizations (e.g., National Federation of the Blind, American Foundation for the Blind). It seems reasonable to infer that this is also how most blind people prefer to be referred to by others.

For other countries, see this page.

… or should we avoid using it as an adjective

On the question of consensus regarding “blind experiment” and similar metaphorical uses of “blind” as an adjective, I cannot say. But to the extent that there isn’t a consensus, one can also argue that “there is no consensus” about the use of terms like “dummy variable”, “senior citizen”, and “smartphone”, since Google apparently disapproves of them, and well-known physicist and writer Lawrence Krauss (and the opinion pages of the Wall Street Journal) hold a different opinion. To me that is an indication that “is there consensus” may be the wrong question to ask.

what is the consensus on whether we should avoid using "blind" as a category of persons

I am not an expert on this topic, but a look at this page suggests that “blind” and “the blind” is how blind people in the United States most commonly refer to themselves, at least in the names of their associations and advocacy organizations (e.g., National Federation of the Blind, American Foundation for the Blind). It seems reasonable to infer that this is also how most blind people prefer to be referred to by others.

For other countries, see this page.