Looking at your entries, it seems to me that 2WD and 4WD will always exist. They both have their challenges, and people seem to like to take on both classes.
Off-Road is taking a boost because it is one of the most stable classes. Your Rules haven't changed much for many years, and you've done a good job of feeding in the new technologies. The Rules on control tyres are also very attractive to the masses of average drivers, as well as newcomers. That means you can attract new drivers because they can buy what's needed to get going easily, and know it won't be out of date by the following month.
Off-Road also has built in limits to what will work. Primarily that is the level of grip - no matter how much power you have, there's a point at which it doesn't translate to faster laps, so driver skill counts for more than depth of pocket.
I've reached the age where standing out in all weathers, and cleaning cars, aren't my idea of a good day out. 12th was my original class, and it's where I enjoy RC the most. Nonetheless, if someone asked me where to start in RC with a proper car that's easy to drive and maintain, I'd tell them that they would be having a lot of fun with an AE RC10B4 RTR, a couple pair of UK-spec springs, some 30 deg blocks and a set of the relevant control tyres. For under £200 at a friendly Club, I can't think of another class where that simple recipe would almost guarantee success.
I don't think anything favours 2Wd over 4WD, or that either will be better than the other. 2WD will always rate as one class where the driver is the defining factor - just like 12th really!
