At the time Bitfinex was hacked, they automatically converted the "hacked" BTC balance to USD. It was around $650 I believe at the time of the hack. It would be unfair to measure the hack in today's BTC value because they converted the liability in customers' accounts in USD.

I was a Bitfinex customer when they got hacked. I lost 30% of my funds on that day. I couldn't be happier with how they handled it. They paid me back in full and did the best they could with the situation they had. People being upset with them over it is insane to me. As far as I can tell, it's mostly people who had nothing to do with it spectating from the sidelines. If an exchange you use ever gets hacked, I certainly hope they do exactly what Bitfinex did, for your sake. And you should too.

Bitfinex already fully financially recovered from the 119k BTC theft by repurchasing the last of the BFX debt tokens a few months ago.

Source?

Edit: found this: https://www.reddit.com/r/btc/comments/7e1840/the_30000000_us...

It seems like people did in fact notice the $30m being deposited on Bitfinex and being used to buy Bitcoin, all before it was known to be stolen. Difficult to confirm a thing like this, but I wouldn't bet against it.

But since Tether Limited are the ones who back the tokens with real dollars, they can effectively unilaterally pressure anyone to upgrade the client. Those who don't upgrade and accept stolen tethers will be left with worthless unredeemable tokens.