I do not think so. I see it akin to buying a smoke alarm.
It is a question of playing the odds and I would expect the relevance of such a fund diminishes over time. Most divorces happen within six years. (per some FL bar stat somewhere I can not remember exactly where I saw it.)
However, since marriages are happening with the men being older, it makes sense to have certain items before marriage IF possible. Buy a house. Start a pension. Put aside cash.
As for prenups, they tend to work best for "items" rather than concepts like alimony or support. They also work better earlier in the marriage. A two year old prenup is different in divorce court against a 12 year old prenup.
We should look at this from a positive slant. Despite the much vaunted marriage strike (personally I think it is a strike agains marrying liberal women rather than just marriage), men are making preparations so they CAN get married.
These men are not saying no to marriage they are saying to to being unprepared. Besides, the "oh sh*t" fund can be converted to a college fund for the kids or pay for that surprise second honeymoon or that dream cruise where the captain marries you two all over again.
The wiring in your house doesn't suddenly get all lax and sloppy when you put in a smoke alarm. It doesn't know the difference.
A pre-nup or a secret divorce fund, however, means that one or both parties know they are not really committed to the marriage, and therefore are less likely to work at it if problems (or a 'better' offer) come along. The same way you will be much quicker to, say, quit a job if you know you've got something else to fall back on.