Yes it does, but a little goes a looooong way to Google.
I've also been starting to notice that having custom HTML / CSS is boosting things more than before for smaller sites.
Also, even if using JS for SPAs doesn't matter to Google there is a reasonable long tail of other web crawlers that may or may not be helpful to your ends and you'd be surprised at how many of them just use mechanize or nokogiri instead of something more robust. Basically it comes down to cost, last time I was in the custom crawler trade it was around 50x more expensive to do things with a virtual dom than it was to either straight parse the HTML or figure out the main API calls JS was making from the browser that actually had the data I needed and just run those.