Unfortunately there was no API with data on which intersections have traffic lights and I had to build these routes manually in Strava using satellite images.
I did learn in the process that some traffic light data is actually available from the government, but only for selected partners. The Flitsmeister app for example has it and shows at some traffic lights how long it will take for the light to turn green (in a car, not on a bicycle)
Also, https://routeplanner.fietsersbond.nl/ has options for different route types including an option to avoid traffic lights if a reasonable alternative is available.
https://popupcity.net/insights/rotterdam-traffic-light-prior...