Apparently you guys don't ride out west. Blowdowns are part of life.
I carry a Fiskar saw with me so I can cut out 8" or smaller trees. On pack trips, I carry an axe or a cross buck saw, So I can cut out the larger diameter trees. The Forest Service has trail crews that clear trails. But they just don't get down the trails often enough to keep them cleared. With all the beetle kill, and Fire killedc trees, there are many many dead trees and any wind blows them over.
I've run into some Ponderosa Pines laying across the trail on very very steep hillsides. No going around these trees on those steep hill sides and when you have a 3' in diameter tree with branches holding it additional foot or two in the air, Making a 4-5' tall jump, There is no option except to cut it out or turn around.
When I get into the Pick-up-stick area of blow down trees we often get off and lead the horses through the tangle
When the beetles kills large section of forest like this, You just know that good strong wind will lay down a enough trees to block any trail
But even worse are winter avalanches. The snow breaks off trees and carries them down hill and deposit them in large tangles. If that tangle ends up on top of a trail, It can take a week witha chain saw to clear the debris.