People have been cutting springs for years. Decades. Famous builders doing customs &/or track cars. Name any builder. Name any shop. Past or present.
Barris, Larry & Mike Alexander, Gene Winfield, Trepanier, Brizio, Foose, Coddington, Dave Kindig, etc, etc, etc. Even Carroll Shelby's 1st. & 2nd. gen. mustangs.
They've all cut springs. It's so commonly done that it's not uncommon.
Hell, even Detroit Spring doesn't have a problem with cutting coils. ...and they manufacture the damn things!
https://www.eatondetroitspring.com/cutting-coil-springs/
It's not a prob if it's done right or not too much is cut.
In fact, cutting springs increases the spring rate, which is fine with me, especially on a lowered vehicle. I'd rather have it a bit stiffer in the ride department than too soft.
Lowered vehicle = less suspension travel. Seems to me that a stiffer spring would make sense in that situation.
Lowered springs for these trucks may look more substantial by the wire gauge used, but when it comes to performance, all they really do is just mimic that oh-so-soft grampa ride.
Way too soft for any type of enthusiastic driving.
You'll find for everyone that says it's fine to do, there'll be another saying not to.
But then, they're more than likely the same ones that say lowering a vehicle is stupid in the first place.