I think Revolut’s deal is a little bit different because they’re working with a third party provider to get to their rates. But it’s the same deal as Monzo -
From Starling Customer Service
Are there any account fees?
There is no fee to have an account.
We do not charge fees for using your card abroad.
We do not charge unauthorised overdraft fees.
We do not charge you for withdrawing money from ATMs.
And from Legal documentation - Starling Bank
MasterCard foreign exchange rates will apply for transactions outside the UK or online in foreign currency.
This is the new normal, the banks & particularly, the travel money card providers, just haven’t accepted it yet.