I was very impressed in Denmark, where that roundabout approach worked very well. Every car slowed down & stopped for me at the crosswalks.

It turned out that that was because they installed a cobblestone speed bump in front of every crosswalk. Cars slowed down even if no pedestrians were around, because otherwise they were going to pop a tire. It made walking so much safer than anywhere else I've been.

Those don't fix it in my experience. There's one about a quarter mile from where I'm sitting right now and I avoid it when walking because of how dangerous it is. Yes, they will see you crossing... as they almost hit you. They recently redid it to be a bit safer for driving on (before people were unclear on how many lanes it had and which lanes could turn where) but it doesn't seem to have improved the pedestrian experience much.

in practice i find this does not work well at all… for some reason in roundabouts is when cars most feel justified in running down a pedestrian in a crosswalk. sometimes i think they’re just afraid to slow bc of the cars behind them

This. Roundabouts with medians. The answer is (almost) always roundabouts.