I used to use the word "crazy" all the time, until it became apparent to me that it's not particularly kind to use a word that primarily exists to disparage severely mentally ill people. There's no positive way in modern English to call a person "crazy".
As a younger person, I made a similar change regarding my use of the word "retarded" to refer to situations I thought were nonsensical or illogical. I'm now embarrassed to have used that word so thoughtlessly, even though it was pointed out many times that it was an unkind thing to do.
Call it radicalism if you want, but I think it's just a matter of stepping back and reevaluating behaviors I took for granted. You know, literal critical thinking.
We're not yet at the point where people look at the word "crazy" as being wildly inappropriate in the same way as "retarded", but I think it's completely reasonable for people to raise the point that putting it in the title of a book that represents the whole company is not a good idea.
You're fooling yourself if you think Basecamp will be improved by losing 1/3 of its staff, including some department heads and long-tenured employees, as well as its nearly universally positive reputation.