Number of cars. Increase the number of cars, you increase the number of deaths. But any given collision is more likely to be survivable than in the past.

Also, it's not a perfect analog, but a quick search for deer hits and you can see modern cars crumple just fine.

Don't get me wrong... I'm not saying this deer was out dancing that very night, but if you're gonna hit me at 30 MPH with either a flat, unyielding piece of steel with potentially sharp edges and/or rusted spots, or a soft piece of plastic or fiberglass formed to cushion my impact into the engine where the REALLY hard parts are, I'm going to choose the plastic/fiberglass every time.

Edit: Here. Just to back up the information I'm giving you...

The ABSOLUTE number of deaths are increasing, because the number of people and cars are increasing. But as a function of percentage of population they are only slightly above the lowest they've been since the 20's. Modern cars are much safer. Even a bad SUV with horrible visibility is safer to all involved in a crash than an average car in the early 80's. The numbers don't lie.

Source

Edit again: To give pedestrian numbers to go with that:

You do have a point... there ARE increases in recent years, but overall the rate is still nearly half of the rate in the 80s. You are correct the most very recent trend is worrying, however.