Copper vs Galvanized Steel Brake Lines

[2004bmwx53i]

Hi everyone,
During the brake pad & rotor replacement on my 2004 X5, 3i, I noticed the brake hose on the rear wheels are badly corroded. So I ordered new ones from local Napa. The small piece in the middle of the new hose is made of galvanized steel. The original is made of copper. So I thought I'd give a try anyway. I replaced the left rear. It wasn't a perfect fit but it went fine.
For the rear right, the condition wasn't much different. I don't want to replace this one the new one. There's no leak and everything else looks fine. It was such a mess and pain to replace the first one.
The copper tubing has been there all these years and are still intact.
I'm seeking your advice to see whether I made right or wrong decision to replace the hose preemptively with a galv. steel tubing. Where I live, all winter we have lots of salt on the roads.
Have a look at the picture attached of the one I took out and please tell me your thoughts.
Thanks.