Serious? No. I don't seriously expect really safe speed limits to be set up by any democracy that has so many motorists in it. But I do think that's what we ought to do. As a civilisation, we are killing our own children at an appalling rate, just so that motorists can catch up to the back of the next long line of stationary traffic a few seconds faster. In town, slow down.
Look at the scenario you described. A car doing the speed limit towards a marked crosswalk... it's such a familiar scenario that we forget to be horrified. Think about what we're doing here. We have footpaths across the street specifically for people to walk across. And then we have motorists driving straight at those footpaths, at such speed that it would literally be a crime to go any faster at all, at such speed that they couldn't possibly stop should anyone suddenly walk out on the path. These motorists expect everyone else in the world to pay attention, to stay out of their way. God forbid they themselves should slow down! They're 'doing the limit' and that makes it OK.
That limit is obviously much too high. It should come down. Twenty is plenty.
Then let's redesign those footpaths. At the moment there are raised paths either side of the street, and when the path runs across the middle of the street it is lowered. For the convenience of motorists, of course; otherwise they might have to slow down. Well, let them slow down! The path across the street is a pedestrian walkway just like the paths either side, so let's have it at the same height, for the convenience of people using wheelchairs, people pushing infants in prams, people with mobility issues. We'll put a gentle slope to either side of the path so that it isn't a nasty bump for motor traffic. Well, I mean - so that it isn't a nasty bump if the motor traffic is moving at a safe speed.