If people picked/ combed the wilderness for debris/fire wood, would wild fires be as prevalent as they currently are?

nope

most sensible counties clean/maintain rideaways & routinely perform controlled burns to prevent wildfires. Eliminating out of control undergrowth is actually better for forests in the long run.
uncontrolled brush fires are unheard of here, and usually only occur on federal/state park land (who are also bunch of greenie morons don't manage undergrowth) and/or as a result of arson.

places like california on the other hand have practically no land management... and the results speak for themselves...