Not GP but I live in Philly, a very dense walkable city. It is absolutely reasonable to set a speed limit below 35 mph on most of our streets. Especially in residential neighborhoods, but honestly ideally pretty much everywhere in Center City and a good distance away from there too.

EDIT: And in fact most of the residential streets here are 25 mph, and I think only that high because it's the minimum posted speed limit in the state of Pennsylvania. (I'd like to see that lowered personally, and more importantly some traffic calming that's actually effective.)

The UK has 20 mph limits in many residential areas, and they are often quite popular with (most) locals, who specifically ask for them.

In New Orleans unless otherwise marked, streets with a neutral ground (median) are 35mph and without are 25mph. I'm usually pretty happy with that arrangement as both a motorist and pedestrian.

The default speed limit throughout all of Manhattan is 25 mph.

91% of the streets in Portland have a speed limit of 30 mph or less.