Oswald saw a major resurgence with the release of the Epic Mickey video game (and its sequel) which released in 2010, but had some buzz going on back in 2009. That game was Oswald's first appearance since 1943. So, going on that momentum, Disney decided to start marketing the character. And why not? A new crop of 'fans' emerged, even people that never touched the video game. Because the game led to news stories, and people googling the footnote and fans can grab onto what used to be a footnote and feel superior, like they are more in-the-know than someone who just likes Mickey Mouse. It's hipster culture.
That said, Oswalds shorts are pretty great, and yes I've actually seen them.