I think that MuleSoft is a really great business, although I wouldn't use it personally just due to not being in the right industry. For back-office environment with tons of point 2 point integrations, it just seems to make sense. Business model is good. Once you're in, going out is really tough. This is exactly like the SFDC app cloud.
I'm in the right business and I still don't understand why I'd ever need this kind of software.
We also use it to transform data from different services when we do integrations, especially old school SOAP ones that we don't want to support directly anymore, and have been replaced by simpler to manage and develop REST APIs. Mulesoft is pretty good for that kind of thing.