True, but the big networks process far more transactions than stripe does, have access to more data (where else has this card been used lately, has the bill been paid, has this customer used the card in a shop abroad, etc), and seem in a better position overall to combat fraud.

The network also has access to the account holders phone number so can actually call to validate risky transactions.

Lower fraud rates would also make issuing banks more likely to choose visa over MasterCard, so be a competitive advantage.