Ehh, the Hindenburg had a flammable skin. Barrage balloons from the World Wars were most often filled with hydrogen and yet were extremely difficult to ignite or take down even with purpose build incindiary ammo for that purpose shows hydrogen balloons can be safe. Often they would be riddled with dozens of holes but still take many hours for them to lose enough hydrogen to float back down to the ground.

The only real downsides are slow travel speed and vulnerability to extreme storms since there arent many places to put it with a large enough hanger even with days of warning beforehand.