If everyone stayed home because they thought their vote didn't matter, things would be even worse than they already are.

Of course, but it's the same issue as we see in any other debate like climate change or whatever else. Individual choices matter, but only when those individual choices are done as a large mass. My impact on the climate or the election or anything else as just me is basically non-existent, but if hundreds of thousands/millions of people all made the decision to impact their lives individually despite this then they would make a difference. It's a weird balancing act and that's my issue with "just vote" rhetoric is that it lacks this nuance.

Also yes of course the presidential election isn't the only one, but Hillary was only on the presidential one.