Just to add to Paul's comments, we technically support point lights now, but performance would be woeful with more than a few lights. (And could you imagine if we only allowed half a dozen lights or simply culled the extra ones).
So our DX12 and raytracing work provides the necessary base to then add efficient new lighting, and that is getting closer.
Of course, if we could convince everyone to become Trainz Plus Gold or Standard members, we'd be able to hire a new engine dev and whip this up by year end.