Why did Nikon double down on FX when the trend is toward smaller cameras and lenses?

My $0.02 in regard to the "doubling down" issue...

Nikon is trying to lure DX system users into the FX system.
That is one observation and I base that on a couple of other observations:
1: The DX lens line up is lacking (perhaps on purpose?)

2: The D300/300s line has yet to be updated (and the D800 and D600 were released first to try and pull the D300 users into the FX system).

Will Nikon release a high end DX camera to replace the D300? We'll see. In the mean time - "Lookie here Mr photographer" (wink wink/nod nod): The svelte D800 and D600 are the "best", the "biggest" the " " (fill in the blank).

In 6 months to a year or so - Rinse and repeat.

As far as the "vacation crowd" goes; They will always be there to buy inexpensive/less expensive cameras than the DSLR. Nikon, Canon and all other camera manufactures know this. That is why every other year a newer/sleeker/sexier/fancier (and usually more $ expensive) replacement comes along - REGARDLESS of the genre (P&S/mirroless/DSLR). If 6 megapixels was good 10 years ago and 12 was good 5 years ago obviously 36 is good today and tomorrow - well...?

The camera makers know their markets. Supply and demand...