Are public transportatio metrorail listed on this site as often as school buses, motorcoaches, RVs, conversion vans, and minivans?
a) yes
b) no

When you answer, can you give me a reason why that is as well as an explanation?

We don't list trains and other vehicles that ride on rails.

So trolley-buses, that have tires and are powered by power lines above are acceptable, but regular trolley cars that ride on tracks are not.