1874 is dead and buried, so is 1925 except for vague references. WTS keeps changing doctrines. Heck, they changed things about 1975 and people deny what is in print in a 1969 Awake and deny everything said at conventions that is not in print. They will eventually ditch 1914.
The problem is that GB predecessors hitched all their anchors to 1914. They took it from the end of end times to the beginning of end times, to the invisible return, to a supposedly clear mathematical Biblical proof involving 7 times. They tied the anointed resurrection to 1914 and still tie the current definition of "generation" to it.
My point is that they dug in too deep. Changing things nowadays is slower because every old reference to doctrine is right at everyone's electronic fingertips. The overlap shows that current GB members preferred to double down (dig even deeper) into the established date rather than ditch it. They bought time. My guess is that they won't change 1914 in their lifetime, but pass it on. Somewhere down the line, when membership is falling, they will tackle this dinosaur.