1. People are CONSTANTLY dying in carriage accidents, which I have to assume is due to car accidents being the like, unmarked form of accidental death in real society and people not wanting to put in more period appropriate deaths for some reason.
2. People are constantly complaining about and/or using isekai cheat knowledge to improve carriage suspension quality
3. There aren’t that many clip art carriages I guess so the same ones tend to crop up repeatedly like character actors

Near the school (and about 5 mins walk away from my mums house) is a small green that has this kind of dip in the middle. The story goes that back in the Victorian times that used to be a pond, but there was a tragic accident, a horse drawn carriage overturned and plunged into the pond drowning a lady. Now, extrapolate this out and I guess yeah there’s loads of people during all the time to tragic back story altering carriage accidents back in the day - you gotta 100% give that one to fantasy isekai mangaka.