When it's broken, you say there's nothing to fix."
Shouldn't it be , from a grammatical perspective, "that's what's crazy"
Because crazy is not a noun (as in "I don't know what your problem is").
"that's what crazy is" is not formally correct English for the reason that you mention, but it is acceptable in informal/casual English, meaning something like "that's the definition/meaning of 'crazy'". Thus the meaning is slightly different from that of "That's what's crazy".
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"that's what crazy is" is not formally correct English for the reason that you mention, but it is acceptable in informal/casual English, meaning something like "that's the definition/meaning of 'crazy'". Thus the meaning is slightly different from that of "That's what's crazy".