Sounds like gross negligence on the part of the truck driver that cut off the motorcyclist. Why does the article say "accident"?

"Why does the article say "accident"?"

Because it's unlikely the truck driver did it on purpose? The correct term is "collision".

The motorcyclist had the right away, I’m sure, but he is the one that was killed.
I try to teach my kids when learning to drive that even if you have the right away it is important to plan ahead and be prepared to slow down if someone pulls out in front of you. This is especially important on curvy roads with a lot of blind curves as well as quite neighborhoods with stop signs for traffic going a certain direction. Someone may not stop for a stop sign but in the end it may be you that gets hurt, or killed even if you’re in the right. Always be prepared for unexpected cross traffic, never assume you have the right away and that it’s OK to just fly through intersections or around blind corners even when you technically have the right away.

"Neves was headed west on Highway 84 when he ran into the hood of a truck turning from eastbound Highway 84 onto a private driveway"

It's certainly possible that the truck driver swung out in the leftbound lane to get into the driveway and didn't see the motorcycle coming. It's also possible the motorcyclist was going much faster than the speed limit as he came around a curve and couldn't slow down in time. On weekends especially motorcycles often go way over the speed limit on this stretch of 84.

Without more details, we really can't know which scenario is the more likely.

[Post removed, please don't speculate.]