Here’s the condition of the front brakes when I got the bike.
Despite appearances the brakes actually worked.

I bought a new disk rotor and disk pads, and rode it like that for a year or so.

I replaced the hand lever and hydraulics with an eBay unit.

But I definitely bought the hydraulic line from a local professional supplier (it cost more than the original bike, but I’d like to know that my brakes will work in an emergency)

As an added bonus, the shiny braided finish works well with the brushed metal tank. It’s all about the aesthetics.