> Whatever operations Coinbase had with Bitfinex were either to support market making activity or as a service for Coinbase's institutional customers to directly access bitfinex via their platform.

How do you know?

Coinbase didn't halt trading or withdrawals during the Bitfinex hack.

Somehow I think Nathaniel Popper would have been able to put that fact directly in his NYT article instead of a throw away tweet if there was a material impact. Heck he wasted a paragraph quoting one of Coinbase's board of directors on the risks of unregulated exchanges like bitfinex versus Coinbase.