It's still an improvement, since before they didn't obey the 30mph limit.

25mph is much better than 35mph.

My experience/estimation is it's still > 30mph they are driving. :(

Automated speeding tickets will fix that quickly

Indeed. And automated driving will end a great deal of greed based revenue as well. And given the sensor data, proving lack of violation is trivial.

The $64k question is: what will states and counties do without police citation revenue?

Automated enforcement revenue will be much higher

Indeed, but when the automated system driving verifies real-time what the limits of the road are, it is trivial for an "Auto" to dispute and provide evidence.

The only thing these auto-scammers would get are human drivers not driving precisely and accurately.

Generally it only takes one driver wanting to stick to the limit for everyone else to do so too, because overtaking is contraindicated. Which isn't to say that it never happens :(.

I live in Edinburgh, which has been gradually introducing 20mph limits over the last couple of years, and I've actually taken to them much better than I'd expected to: they don't reduce my average speed all that much, especially as the arterial roads are still 30mph, and they're much more pleasant when I'm out of the car.