Plenty of people can't get credit cards.

Plenty of people can't even get bank accounts.

It's absolutely comparable lock-in.

Every bank and credit union I've banked with provides free checks, a free debit card, and no fees for ATM cash withdrawals.

If my bank gave me a free smartphone, I might be OK with using it for commerce. Maybe, maybe not. I don't know if I have a strong opinion on that one.