how to filter that is immuteable or is it already immuteable?

Question

I add a state like this:

      setSelectedColors(prev => [...prev, color]);

but if I remove a state with filter is this already immuteable or had I forgot anything ?

      setSelectedOptions(prev => prev.filter((el => {
        if(el.color === currentColor && el.size === size) {
          return false;
        } else {
          return true;
        }
      })));