Does it mean the same if I use "final" instead of "ultimate"?
No, it would not mean the same thing to use "final" here instead of "ultimate" because in this case, "ultimate" does not have the meaning of "final". "Ultimate" in this sentence is used to mean the most extreme, the best, or the biggest. Here's a couple examples of "ultimate" in similar contexts: Ex: I have a lot of hopes but my ultimate hope is to get that job. Ex: The ultimate purpose of the company is collaboration.