It doesn’t seem like registration is enforced in any meaningful way.
And most cops no longer track this stuff visually either. It's my impression that most patrol cars today have autonomous cameras installed that check every license plate in their field of view for expired registrations and outstanding warrants.
Many police cameras likely do facial recognition too. (Numerous states subscribe generously to commercial services that sell face recog with no independent certification of accuracy, which is famously terrible, like a 90% error rate.)
Or dropped the requirement for front plates. The best part about front plates is that they can drop off and remain at the scene of the accident (or embed themselves in the bumper) during a hit-and-run.
But insurance coverage can fluctuate over the course of a year, because unlike with health insurance, there's no annual enrollment period; people switch insurers, or miss bills, or sign up ruthlessly for a month of insurance to get past the state bureaucracy and then just never pay again.
There's the SR-22 system, which is a court order to maintain insurance at minimum levels, which you get for getting repeatedly pulled over without insurance (or, perhaps, for getting pulled over without proof of insurance and then not proving you did get coverage afterwards). But that's not a fix, because you can only enforce it at police traffic stops.
My car is insured and registered, but it has been the better part of ten years since I actually bothered to put a new sticker on the plate. Maybe there are places where cops try to more actively police expired plates, but it certainly doesn't seem to be a thing around here.
anecdata, but in my town of 60k people, any one drive I do I couldn't even count on my hands the number of expired temp tags (I've seen over a year old), and expired registration.
It really _feels_ like people don't get pulled over for that anymore.
the poor or un-insurable go without and just hope they aren't caught
I imagine past some threshold, even if the cops do know that someone isn't insured it's just not worth running a whole anti-uninsured-driver campaign.