I disagree.
The Robinhood system includes their disbursement process.
In this case, someone with access to a username and password managed to, without passing any of the other typical 2FA checks in finance (Calling the the account holder, snail-mail confirmation, actual 2FA tokens) managed to get Robinhood to wire them money.
This is absolutely a compromise of their disbursement system. If a bank gave all my money to some random asshat that showed up to a branch with my debit card, the blame for that lies on my bank.
This is typical liability laundering.