Presumably multi-causal (economic desperation, rising metal costs, perception that the crime won't be punished, getting the idea from others, etc.) but at least one component is probably the rise of high-powered, battery-operated tools. Battery tools are so much better today than they were even 10 years ago. In the picture from the article you can see the guy using a battery-powered reciprocating saw. Not long ago, an approach like that wouldn't have been feasible.
To your point, you can get a Stihl Cutquik TSA 230 Cordless Cut-Off Saw for ~$500-600, and this will make quick work of anything getting in the way of scraping. I've cut through thick steel with it like its butter (and the only portable way to go faster is something like a plasma torch, depending on material and thickness).
I helped cut off the tail cone of a Boeing 747 (former United tail #882) using of those at the Tupelo MS boneyard a few years ago. Well, actually I drew a sharpie line and said “cut here” and someone did.
There’s a pic of the result of our handiwork on Airliners.net, I have much cooler and closer pictures with sparks flying and non-OSHA approved crane rigging being employed that I unfortunately cannot share, but yes, hot knife through butter described it.
Planes are basically made of beer cans though. Sawzalls really struggle with thicker material because the reciprocating nature makes for fuck all chip evacuation.
Ironically those battery-powered tools used to steal metal were often stolen themselves, either shoplifted from hardware stores or taken out of construction workers' trucks. Local law enforcement doesn't take those minor thefts seriously and this causes more problems.
It's hard to impress upon people how big a change in capabilities there was when things like Milwaukee's M18 line came out and became common. I can remember when it was unimaginable to have a battery powered sawzall worth a damn, and it's even crazier to think the battery powered M18 impact guns now often will do better than most pneumatic ones. The 18 volt lithium tools (Milwaukee, DeWalt, Makita, Bosch, etc.) are everywhere and cheap now and kind are revolutionary in what kind of stuff they enable.
I went to an NHRA drag race event this year and watched some mechanics rebuilding an engine between races, I was surprised to see them using M18 impacts, but that’s a hell of a lot easier than dragging around a compressor and a bunch of lines!
Yup, all sorts of bike locks are totally useless now.
In the EU they make hard-disk manufacturers pay tax for the inevitable copyright theft. I think that's nonsensical but I daydream of having that for makers of these things (and glass bottles).
Maybe that needs a sawzall. But getting into a utility box only took hand tools. Only recently after thefts have gotten so bad have they been welding these boxes shut. When they stole all the historic lights off the Hyperion Bridge in LA, it looks like they were merely unbolted:
