So first: why are the banks/fiat bad?
Second: How does Bitcoin fix this?
Third: What would make the average consumer care?
Fiat is inflationary. It's far too tied to government politics.
In most countries, on short term (from earning the money until it's spent) the consumer won't see much of a difference. But there are countries (Venezuela is the top example) where the local currency is a bad joke.
In such countries people can probably buy US Dollar for safety if it's available. Bitcoin is another option.
On long term, even in US one can see that the value of money is decreasing slowly (inflation). Bitcoin is deflationary and should "fix" that, because it's designed to be deflationary.
Yes, I know, this may sound fake in a bearish market, but .. if you look at the averages, you'll see this.
And in the days the markets turns bullish, Bitcoin is also a good investment (although quite risky, tbh).
Average consumer? Well, for now the "history" has shown that the average consumer couldn't care less. He jumps in when everybody shows Bitcoin rising, then, when the rise ends, he will sell, possibly on profit, possibly not. The technology that allows you send anywhere millions of Dollars worth of Bitcoin for the fee of a few cents, the deflationary nature (max 21M Bitcoin ever and clearly some do lose their money forever), the fact that more and more merchants start accepting Bitcoin for their goods/services, like any other proper coin, these are not important for many, unfortunately.