Railroad crossing have red flashes, which triggers something regarding photo sensitivity. It's even worse when speeding up the game as the animation speed (hence flashes) speeds up too.
I mentioned it here when a developer video came out and one idea came up, which is using German crossing signals as those have a fixed red light (no flashes). That seems like a good solution, possibly made optional with the disable flashes game setting.
https://discord.com/channels/803508556325584926/860289362620842034/1365672043898732656
Even through I don't get seizures, it's still headache inducing for me (enough to force me to stop playing), so my personal view is that this is a game breaking issue, or at least an issue, which makes trains unusable (which I suppose is close to the same thing).