Trains

In all fairness, we do have a few objectively nicer things, like level-boarding for wheelchairs and strollers into LRT carriages, and pantographs rather than trolley poles.

But we did lose 100+ MPH operation in the 30s, when the 79 MPH track limits came into being for most railroads.

So in total, if that's all we've progressed after a century, then yeah, we haven't gone very far.