How can crypto be a dollar replacement when everyone uses the dollar to tie its value?

I’m new here and one head scratcher for me is that the value is tied to the dollar. If I want to do a payment I look at my wallet and it shows me the current value in USD. I read a lot of comments about how crypto is important for when the fiat economy is crashing. Well if the dollars value goes down to 0 then any crypto is gonna be worth 0*

I just want a stable currency that is non inflationary and can’t be printed more of by a government. Being tied to fiat confuses me. Please help me understand the solution here.