Though the goalposts shifted from "cannot build bike lanes without destroying thousands of homes and businesses" to "there is no visible impediment for pedestrians," even that understates the extent to which designing for safety and comfort make a huge difference in usage. Walking along a high-speed road with no barrier is a radically different experience from walking along a low-speed road or a road without cars, or even a road with a barrier for pedestrians.
Just like widening a road draws more traffic, creating pedestrian-friendly and cyclist-friendly spaces draw more pedestrians and cyclists, so a lack of perceived demand given current infrastructure doesn't mean much.
I provided two links, just two arbitrarily-chosen out of many, and yet even then the comment to which I'm responding focuses on disagreement with only the first, which is apparently an unimpressive case study because the current shops are too expensive. The seven examples in the second link might have helped, but I'm perhaps not. There are many, many more resources about how to build pedestrian-friendly streets[0] specifically, and a lot of information available about how to build strong towns[1] generally, if one is actually interested.
About light rail, I described the system in suburbs of Dallas, Texas, pretty far from Europe, which it turns out are even less dense than Sacramento, California[2]. And yet my experience with the existing light rail lines is largely positive. While they aren't jammed full of people twice a day like trains I've experienced in other cities, I've definitely been on the train when there was standing room only more than once. It seems as if systems well-designed to match the areas might be more effective than systems that are possibly political pet projects. Where tracks and stations are located and how much tickets cost are all choices made by someone somewhere, and sometimes those decisions are better made than others.
Dallas is very, very far from an ideal place for mass transit, given cultural factors and topography and geography that is very spread out, and yet three different train systems (for Dallas, Denton, and Fort Worth) seem to be able to work together and provide popular options for a good number of people anyway. It can be done, and it might help to focus on success stories more than perceived failures.
All in all, I find city design fascinating, but obviously many people don't.
0. https://nclurbandesign.org/pedestrian-friendly-street-a-grea...
1. https://www.strongtowns.org/streets
2. https://www.opendatanetwork.com/entity/1600000US0664000-1600...