The vast majority of users aren't using random characters, so how would they know to say that to begin with? Are you implying they try that line, idk, 10,000 times until it (maybe) works?
Support: what is your fathers middle name?
Hacker: Michael
Support: sorry that is wrong
Hacker: oh shoot, I forget I always put the incorrect information in this one... i can't remember, did I put a fake name or random characters? Or was this the one I put a bunch of words into?
Support: yeah, it looks like random characters... let's move on
"Computers are hard, and I'm just not very good with them!"
attacker accesses recovery answers for site A. Sees that it is random characters. Attacker has access to site A.
Attacker phones sites B,C,D and E, trys social engineering. Attacker now has access to site B,C,D,E also.