As Deus Naturae pointed out, median household income is still below its prerecession peak. Of course, the typical voter isn't looking at statistics when they decide how the economy is doing. It's more of a personal feeling.
Your average white, working class voter just isn't that impressed. There was a nasty recession. He probably faced a cut in hours or benefits even if he didn't lose his job. Meanwhile cost of day to day items (as opposed to durable goods) has increased quite a bit. However, things aren't quite so bleak as they used to be. His friends and neighbours are finding jobs again and some of them are decent paying. He might be seeing raises for the first time in a long while.
What does that guy think of the economy? He might be optimistic, but he sure doesn't think its booming. If the Democrats were acting like its 1996, it'd come off as tone deaf.
Yeah, that's the status quo argument that's been getting used for years and is why Democrats are still getting hammered. Right-wing policies drove the country off of a cliff. The argument shouldn't be "is the economy better in every metric than it was before the Recession started?"; it should be "How much better is the economy now when compared to where it was after conservatives ran it off a cliff?".
C'mon Griff, you know better than to suggest that a politician run against things that happened 5+ years ago. Let me guess, you think Carter should have spent the 1980 election talking about Watergate