Someone ELI5 how a layer 2 isn’t just like a visa providing their service then recording all of our activity on etherium?

So help me understand layer 2s and why they are better than our current system.

From one aspect yes I agree the public aspect and transparency of a layer 2 can be helpful. It rips away all the possible smoke and mirrors a company has and let’s us see exactly what’s happening.

The thing I don’t get is if layer 2s are doing their processing off chain how is that different than what happens now? What are layer 2s doing differently than our current payment process that they can ever be cheeper than using a credit card? It’s seems like visa would just do their process now and add an extra step of reporting it to layer 1. Is that right? Where does the processing improvement come in? Is the only improvement that it should be permission-less and be recorded on a public ledger?

Those are good things but it’s just hard for me to imagine why that would be a big enough idea for most applications.