Its just not true. Bikes get stolen a lot even when they are locked.
But There is not a lot of violent crime in Switzerland, so you can walk around everywhere without any worries.
I read a lot of books already but sometimes I prefer a blog post where you can read about a certain topic for 20-30 mins instead of dedicating hours to a book. If I‘m really interested I will order a book about that topic. And also a lot of these blogs have book references, thats how I find out about these books sometimes.