Confused at first and then astounded perhaps that there's a standard declarative approach. But never angry. And they get paid to read my code, so if they have any such emotion, they know that they best keep it to themselves.
Also, non-programmers dig XSLT specifically because it's not "code".
I manage a team of reporting analysts who have to maintain data feeds from our clients to brokers. They are from business and accounting backgrounds and use XSLT for it all. They don't need to worry about build steps or any of that junk, we just store the transforms in a database and they use IntelliJ to incrementally build out the files to the brokers specs, and we can display the transforms in a UI to other staff so they can know whats going on whenever there are questions.
Hundreds of reports, couldn't manage it all without XSLT.
Also, non-programmers dig XSLT specifically because it's not "code".