In his old year cabaret show, Peter Pannekoek stated the buttons near crossings don’t actually do anything, they’re just there to just pacify people. I’m fairly certain they in fact do work, though for cyclists they’re mostly redundant: the magnetic loops in the road surface detect cyclists. Only for lightweight carbon bikes a manual button is still useful.
Am I correct in my assumption?
They certainly do something where I live, one button was broken for like a month and I had to cycle through a red light every day. I could do it sort of safely at least, because I knew when it would normally turn green in the rotation.