Am I going crazy here?

I am attempting to create a couple of small integrations with a medium size company's software.

I finally got an api key from them, but it came with a disclaimer that basically said "all development should be done in the dev environment (no fucking shit) because incorrect PUT calls will cause 'bad data' and 500 errors in the prod environment. These db issues can take weeks to undo…. yada yada yada."

This is ridiculous, right? They are essentially saying that zero validation is being done on the data that ends up in their db, right? I haven't worked as a software developer for several years, and I am not super familiar with web development, but this seems like a gigantic oversight to me. I am wondering how is this even possible? Shouldn't using something like entity framework prevent this by default?

Or is this not as big of a deal as I think it is?