That may say MAN but I think it is a Neoplan. It looks like the engine is in the rear section; Seattle has several articulated buses with the powered wheels in the rear, and the last snow storm, they were everywhere but straight.
Yes, those articulated buses with rear engines are terrible in an ice storm. We had an ice storm last winter and the local transit agency had something like 200 buses crashed. The block I work on had 4 articulated buses crashed around it. The rear engine causes the bus to jackknife on the ice.
We have a fair amount of snow and it never causes much issue with articulated buses, but ice is a different story.
Seattle snow is different than anything you have seen; we generally only get snow at 32 degrees so you several inches of slush. It filled the treads and is mostly water under the slush so just no traction.