I spent a year not working and had no trouble lining up dozens of interviews when I started looking. However, it did take several months before (a) my interview game was up to par, and (b) I found a company I actually wanted to work for.
I suppose sleep and videogames aren't great answers. Taking time off to travel or explore some other interest is almost certainly fine in SV.
Ultimately, I think most places are so hard up to find qualified candidates that as long as you pass the interview and don't come off as a total slacker, you're probably fine. But if you're career-minded and applying to a place that has their career tracks worked out (read, not most startups), you probably want to give that impression to your future engineering manager.