I don't think that is really true. In principle, a slower train is quieter, but a tram usually has very tight curves in lots of places, resulting in screeching,

I don't think that is really true. In principle, a slower train is quieter, but a tram usually has very tight curves in lots of places, resulting in screeching, as opposed to a (modern) mainline railway which has much wider curves. A tram also needs to run closer to the homes, to still be attractive despite the lower speeds, increasing noise levels at the homes and also requiring more road space near people. Meanwhile a mainline train is much faster, thus can run farther away from home as the access penalty is offset by higher speeds. Low-floor trams also often feature more screeching due to the inability to use conventional bogies. Anecdotally, in germany, projects to (re-)build trams in cities often fail over local protests, while rail reactivations don't usually succumb to that. HSR does get a lot of local protests, but (IMHO) not really because of the noise and fails less often compared to trams.