You, the bank customer sign up for a service (like RocketMoney, Plaid or other fintech service) that you then provide with access to your banking information. That service then sends out API calls to get your data from the bank, and routinely updates is (maybe in the background, maybe only when you open their app). Right now, the third party has cost-free access to your banks API and data.
The old rule is effectively, the customer owns their own data and if they want a third party to access it, it should be cost free.
The new rule is the old rule is gone and the bank owns the customer data and if they want to charge folks to access it, so be it.