No chargeback is a bad thing for consumers who loose the safety credit cards offer. If consumers prefer the safety of credit cards then the merchants will ignore bitcoin.
Bitcoin must offer something that benefit people before they want to use it. No such benefit exist today and therefore there is no interest in bitcoin.
What is a credit card? It's a payment processor for fiat transactions. Well then there will be payment processors for bitcoin transactions much like bitpay that can offer protection against this.
You are right. A credit card is just a payment processor and the underlaying currency is not very interesting. I dont care what the underlying currency is called. I only care about how i can use it and if it is accepted wherever i need to spend my funds.
At the moment there is nothing with bitcoin that makes it better than my current payment processor and therefore is will not get used.
What about identity theft? Everytime you pay with your credit card the merchant has to secure all the information you have to give.There is a reason why brands like Target, Sony, Home Depot, Asley Madison attract hackers like flies.
Credit cards are working as a pull mechanism. With all that data hackers can empty your account very easy or sell your in deepweb and other criminals use your datas to do some other bs.
Bitcoin is working as push mechanism. No one can withdraw from your wallet without the private keys from your public adress.
If that is not a big advantage I would ask myself what else.
First: Is the targets of this mainstream adoption very conserned with those questions?
Second: If someone hacked a site and got my credit card info i just reported it and i would get my money back. Also for bitcoin to be usefull for most people you have to use online wallets. Then you get the same problem with hacking, but no chargeback to save your ass.