A developer cannot promise everything and especially not for free. In the 90s when games had to be finished at some point

extra features were sold as expansion disks and today there are DLCs.
The way I understand it, camshaft could have said: no flat engines, no diesels etc. The other option is DLC after the game is finished, which is the normal practice.
V16 and other stuff as DLC is fine with me too. I was already wondering how I would get them because I did not become a premium user.
P.S. It's impossible to miss that V16 was promised as a bonus item and it's written everywhere all over the store, so this is really not the same as day one DLC. Giving it away for free would be a real kick in the groin for those people. I am rather surprised that they put up with waiting so long.