I got interested in modelling because of Trainz. Initially, I was learning the modelling itself through various Blender tutorials, then I tried to play a bit with "legacy" textures, and eventually decided to learn the PBR flow. I think it was a very good move. But I want to tell a bit about the difficulty of this flow.
From the perspective of the last couple of months, I see that PBR flow is not actually that hard to learn. In fact, if you start with simple objects, you should be able to achieve nice results after I don't know... maybe one or two entry-level tutorials. And further discovering of the features gives a lot of joy. I was extremely happy when I learned how to create a reallistic snow cover effect. It turned out that I had to use exactly the same technique I had already learned to apply dirt etc. onto the walls. Later, I wanted to have a mossy wall. I had a brick wall material, and I realized that I just need to use the same technique that I used for dirt and snow, and within minutes of expermenting with switches and sliders I had my nice-looking mossy brick wall.
And what was hard?
1. for modelling, you have Blender which is both free and powerful. For PBR, there is currently no good free alternative, and you have to put some money e.g. to buy/subscribe Substance Painter or similar tool. There is an open-source Armor Paint which is being developed. I tried it, too, but it's not that mature yet as Substance Painter. And SP comes with a rich library of ready-for-use materials. Without such a library, doing anything in PBR is a complex task.
2. lack of good video tutorials that show the flow step-by-step, and that are Trainz-oriented. Yes, there is wiki, but you need to spend some time to connect the dots. For example, the wiki article about exporting the model from Blender to Trainz assumes that you already have the model and a PBR texture. But it does not explain, how to create that texture in the first place. It won't show you that you e.g. need to firstly model the object, then create the UV map, and then cut it in a proper way, so that you could apply the materials easily in Substance Painter and this is how you get it. The articles about rendering optimizations are in yet another place, but you need to read them, too, to understand why it's generally better to pack everything onto one material rather than 7. Once you know the steps, things are easy, but it took me almost a month of trial-and-error and ~4 attempts to figure out how to do it right and finish my first PBR object.
The cost of tools (point #1) is something that we need to accept at this moment and everyone has to answer themselves "do I want to pay this money". But point #2 is achievable with the help of the community and people who already learned the PBR flow, and it could help people switch to PBR or attract new modellers.
