I'm highly suspicious of such a claim. So you're saying that in a 25mph zone, a cop will pull you for doing 25mph because you're holding up people that wish to exceed the speed limit? Not in any U. S. state that I've lived in.
https://www.ticketcrusherslaw.com/traffic-ticket/speeding-ti....
If somehow you got a ticket for this, you’d just say it was necessary for safe operation, after all, why else would there be a speed limit in the first place?
So yeah, I still don't believe you that I'd be fined for driving 25mph in an area, where 25mph is the speed limit.