This is almost exactly never where I want to go when I click that button; pretty much every time I'm clicking on the site-switcher, it's because I want to access…
- …the meta for the site I'm currently on
- …the chat for the site I'm currently on
- …one of the other sites I frequently use
These are all things that the site-switcher is great at doing. I'm happy, you're happy, everyone's happy. Stackexchange.com, on the other hand, doesn't really give me convenient access to any site metas, any chat rooms, or even really any other sites.
Sure, sometimes maybe I want to go to check out the hot questions feed, but if I was going to do that there's now a big "Stack Exchange" logo on the top left of the page that takes me right there (and much more intuitively). Having the site-switcher point there by default might've made sense in the old top-bar before there was a dedicated link, but right now it's just redundant and ultimately only exists to cause pain and frustration for all involved.
If you must have that icon point to somewhere, maybe a page that basically duplicates the site-switcher functionality (Even stackexchange.com/sites would be better; at least that's actually "A list of all 171 Stack Exchange sites" like the mouseover text indicates).