Many years ago I was connecting APIs from ~100 companies into our application, they all essentially did the same thing -- update information in our system based on a tracking number. At this time, about half were web APIs and half were WSDLs. The WSDL APIs were by and large the easiest to work with, I didn't have to write much of any code. On the other hand, the web APIs required me to have a custom flow for each and every one and they could break at any point without me knowing.

I've seen a lot of hate on WSDLs throughout the years but they were honestly really productive for getting work done.