I am an increasingly suburban rider. Olde age and familiarity with surrounding countryside lessening my mileage,alongside more traffic and housing being built hereabouts. If there are more bike thefts(and which I dont doubt),I cant think the stolen bikes are of much value. In the city, it is rare for me to see any quality bike left unattended. Same at places of work: hospitals or the uni. I guess there must be exceptions,but I cant see many people riding and leaving quality bikes to be nicked. I guess most cyclists stay near anything of value,or have it locked up at home. In the smoking city where I live some 30 years back, I was told thieves followed quality bikes and their owners back home: later they broke in to the garages to steal them. At this time it was MTBs or somesuch.
I ride a step thru frame so as to avoid any undue attention. I assume most bike thieves are men and would steal for male demand. Myself and my wife used to ride two contemporary folders into the city. They were stolen. Best ride free with something unattractive...well,to the untuned eye.