[Workaccount2]

The replacement will use modern parts and tools, administered by someone who knows modern systems.

There is no use in becoming an expert in an ancient system ridden with proprietary and obsolete parts, just so you can help one city maintain their ancient system. It's even worse than wanting to become a professional fax machine guru.

[culopatin]

There is no use for so many things… For example there is no use in assuming you know what other people want to do with their time, because you just don’t know. Some people like knowing unique things, or just enjoy learning, or want to be a small hero for a small group of people, or are just curious.

[anon7725]

Keeping a transit system that is relied on by millions of people running seems like a very useful endeavor.

The problem, for an engineer considering this path, is that the gig ends before you want your career to end.