I wouldn't be in the unanimous but more in the it will probably work camp. If I'm not mistaken, my Backwoods originally had a 70.5º head tube and a 75mm fork with a ~440mm axle to crown height. I'm now running an 80mm fork with a ~450mm axle to crown height which slackened the head tube to 70º. Going to a 100mm fork with a ~470mm axle to crown height would slacken the head tube all the way to 69º.

This is merely an example of a situation where it wouldn't work as well as hoped. The trails around here are riddled with tight switchbacks and negotiating them efficiently is piece of cake on my Zaskar but currently requires much more careful planning on the Backwoods.

Taking another degree of the head tube and adding another 6mm to the wheelbase as well as another 6mm to the bottom bracket height would have the Backwoods handling more like a freeride hardtail. If that's what the OP wants, I say do it. However, around here it would have more of a tendency to wander on all the extended granny gear climbs and having to swing another 6 or more inches wider around some of the aforementioned switchbacks would likely put me off edge of the trail and into the trees.