What this Coinbase blog post forgets to mention about leverage is that Coinbase itself is the most leveraged of all.
Coinbase borrows enormous amounts of bitcoins and fiat from their users to carry out speculative shenanigans on the market. One day or the other, Coinbase will fail at their speculations and go bankrupt, taking with them all the coins and all the fiat from all their users.
How do we know that Coinbase is not insolvent already?
Where the hell is their Proof of Solvency?
They cannot keep pretending and make-believe that they still have all the users' coins and all the users' fiat.