Phonepe card could have a different issuing channel and they would have some competition from cuckdfc to in terms of getting the card issued to users.
Two disadvantges (potentially 3) which sbi has over cuckdfc are
1. Lower card issuance friction due to "brand prestige" and few people would stereotype sbi cards being the same as sbi bank slow and clunky
2. Lower existing (also lower % of interested) customer base who are interested in getting a credit card
3. If sbi sprint comes into the picture and overleverage is an issue then they lost the battle already