Dates are becoming more and more irrelevant to WT doctrine, the days of the heavy duty interpretations and conclusions are gone.
The 607 date doesn't really matter in practice anymore. As you say, the days of complicated prophesy analysis are behind them. In its place is a lot of "just around the corner" sloganeering and overlapping-generations nonsense that nobody can explain with a straight face.
Pride, ignorance, and the fear of disfellowshipping is sufficient to keep most of the Witnesses in line.
They may let 1914 slide into the dustbin of history without formally dropping it, just like they did with the thousand-year creation days nonsense that led to the 1975 hoopla. They never formally renounced that view, either. They just stopped teaching it.