A nice looking webpage is the VC equivalent of a 'vanity metric' - sure it looks good, but does it help them source great investments? Perhaps it raises the number of views on their website, but are any of them the high-quality entrepreneurs they'd like to invest in?
Frankly, I'd think that the problem that the top VC firms is not knowing enough people, it is finding enough time to properly evaluate them all. If you're picking a VC based on their website and not their intrinsic business worth or ability to help you succeed, you probably aren't the kind of business they're looking for.