I don't think you understand the importance of BTC being decentralised and trust less. Long story short, if you trust banks/credit card companies/financial institutions more than you trust yourself, then yes, the main benefit for you would be low tx fees.
If you use a credit card to make a purchase
the bank is trusting you with their money, not the other way around. You don't need to trust the bank in any way by paying via a credit card as you have the ability to make your payment in cash, and if they say you owe more then you really do then you can not pay the bill.
What money?? The one they've created out of thin air, but are secured against your income/assets, often with changeable %rates?
Are you saying that it's better to take a loan to buy something than use the funds you own (since it's "trust less" and bank take all the risk)?
A credit card loan is secured by nothing more then your reputation. If you are able to pay off your balance every month then you will generally not pay any kind of fee for using it. The money you borrow when you use a credit card is borrowed by the bank from it's bondholders and depositholders.
When you use bitcoin you need to trust that the person selling you whatever goods/services is going to give you such goods/services after you provide payment. With credit cards you do not need to give any such trust (you can dispute the charge if you do not receive the goods).
The benefit of using bitcon vs using a credit card is the fact that it is cheaper and less risky for the merchant, which should mean lower prices for you (the consumer).