Its always a question of degree.
Removal of the parts that jam the tires on full stuffage is what you want to do, but, that's too mad max for some, and a BL is a way to REDUCE the trimming to fit the same tires.
If the suspension is not getting fully stuffed, say your terrain simply doesn't do that, suspension alone can work as your clearance is only an issue WHEN stuffed.
The jeep guys, etc...and some others, rely on evil uptravel robbing bump stop extensions...so "full stuff" is less fully stuffed, etc.
If the suspension is stiff enough that it simply doesn't LET the tire up high enough in th well to hit, that works too, but, again, that means it's not going up as high.
So, if the way/locations you wheel, some rub on stuffage is not a big deal...tire clearance is just not as much of an issue.
If you wheel where you need to stuff up higher, and have the fenders not jam the tire, etc...remove the fenders/parts that are jamming/BFH the pinch seams back where needed, etc...and call it a day.
If you do a BL, you have LESS of that to do, but, generally, even with 5.5" BS, you have to at least remove plastic, etc, to clear 33x12.5's.
Less BS = more trimming for the same sized tires up front.
The rears can fit huge tires w/o any thing but LESS BS and bending up the wings on the rear stops, etc.
Even in back, if some frame rub is not bothering you on opposite side stuff/droops, OEM BS is fine.
It can jam the tire on hard stuffs though if you have the travel...and less BS/spacers, etc, helps that in the back.