Yep, this is one reason that I think it's also a great idea.
Since Trainz Surveryor has built-in functionality for merging baseboards, why would you need a new server based solution for this task that has already been solved 15 years ago?
Is there actually a user requirement for this? Has it been expressed on the wish/suggestion list?
Aren't there enough other challenges for the next version of Trainz? Yes, there is some sort basic superelevation available now. But for practical use, it's far too complicated to address each individual spline point. And what about turnouts? Indeed, they exist in a superelevated variant, too.
Interlocking. A nice start, yes. But has anyone tried to configure a reasonable mid-size station? It needs a lot more automation to become more than a pastime.
How about train brakes? It had been on the list already. For the time being we only have basic Westinghouse (or have I missed something here?). And Westinghouse was never in use in most European countries. In this respect Trainz is still a game, not a simulator.
We could continue here endlessly. Catenary, for example. Automation again.
Why waste precious development resources on something that hardly anyone needs? If the overall idea is to open new ways to generate revenue then I can understand the motivation, but the counter value on offer for that subscription service doesn't look convincing at all. One of the reasons I think there must be more to it, looking in the direction of data mining.