Depends on what you mean by "mesh". Each road segment is an instanced rectangle that gets extruded and beveled so that it fits tightly against adjacent segments, and then the pixels are shaded using AAA (with a capsule-shaped distance field) so that the result looks like an antialiased wide line with round end caps and joints.
This brought back some memories. Long ago I had to do some AAA for line rendering on some hardware that didn't support line AA natively.
A big customer was furious that they had bought a part that didn't perform the way they wanted, so I was voluntold to fix it.
I was given a ridiculous timeframe to come up with a solution and present them to our customer in a big in-person meeting with all the decision makers. I managed to implement three different alternatives so that the customer would feel they had some agency selecting the one they liked the most. The best looking by far was a form of AAA.
This was one out of several of these big last minute fires I was assigned to solve. Years later my manager told me how great it was knowing that the could throw any crap at me and I would be able to fix it in time.
However, these sort of experiences are why I struggled with burnout during my career, which led me to save like crazy to retire as early as possible, which I did.
For younglings out there: when they ask you to do the impossible, remember that failure IS an option. Push back if you think they are asking you for something unreasonable.