That seems like something good to be able to turn on in a stock kernel, but not with that high a timeout. Imagine your shell failing to start another process for 30 seconds after you're debugging a segfault, or your browser failing to open another tab for 30 seconds after one crash.
500ms would drastically slow brute-force attacks without noticeably inconveniencing the user (and then they can always turn it off manually when doing something like fuzz testing).
30 seconds, predictably? I'd take it any day over that.