I should have been a little clearer. During my uncle’s time DNA testing was reserved for things like rape and murder. And not all of those could benefit from the older testing, so budgets limited when it was used. He was shocked by juries that expected it for things like shoplifting. It wasn’t done, but CSI trained everyone to expect it.
Fast forward and, yes, old crimes get the cold shoulder vs new crimes. Rape kits make up the disproportionate number of old cases getting testing because they are serious crimes, statute of limitations, and more likely to yield DNA results. But they are older and get bumped. The queuing policy needs to be improved.
The expose work that was done over the last year or so showed that it’s not just old rape kits that sit untested. In one example (New Orleans?), the reporter, on follow-up, found new kits that had been tossed in with kits from the '90’s, untested, no test ordered. So it’s not just queuing policy but fundamental de-prioritization of rape investigations.
So serial rapists are low IQ chaotic evil, rather the high IQ lawful evil planners that TV thinks they are. The only reason they keep getting away with it is that there is a social disbelief in victims, and a lack of interest from the police.