In the case of political dissidents in repressive regimes, compromising Tor can also kill.
There was a DEFCON talk about TOR where the speaker advised "All of my friends and contacts in Israel & the Middle East who didn't use TOR -- I no longer hear from them".
This isn't about the performance of the network. They could've brought it offline and that wouldn't have been as egregious an affront. They willfully subverted the network to invade the privacy and anonymity of the people using it. Regardless of the purpose, the potential damage to the people using it for any reason is too great to ignore. Political dissidents, whistleblowers, journalists, lots of people rely on Tor, and who knows how much of their information was exposed as a result.
If it's really that easy to subvert Tor then we should thank the FBI for showing us.