Their dev team is excellent, but the business side and everything related to banking and withdrawals is atrocious. If they ever turn into a reliable exchange, i might return. Until then i'll watch from the sidelines.
The banking is totally out of their hands and always will be unless they buy their own bank, which'll be instantly shunned.
If I were them I would've become crypto only a long time back. Still a ton of money to be made and vastly less head aches too. It's fiat that causes all the problems.
That's not entirely true, given that Shapeshift and IDEX are now enforcing KYC, and 1Broker and EtherDelta got charged by the US government.

Going altcoin-only might have killed their market share too. It's hard to compare to altcoin exchanges like Binance because those exchanges all piggybacked on USDT liquidity. Bitfinex never really had that opportunity -- they're the bank. Without fiat and USDT markets, I think Bitfinex and exchanges like Binance and Bittrex would be much less liquid and much less profitable.