Essential services (banks, government services, public transport) generally still support SMS as an alternative to their mobile apps when there's no completely offline process.
If you can't exist in society without a smart phone already, how is it going to get worse?
Perhaps you won't be able to exist in private without a smart phone. Or there will be some technology beyond a smartphone that you can't exist without.
...without a smartphone that is surveilling you 24/7.