There’s no conflict here. Using a tool to automate what you have validated to be the trivial parts of a production process is the proper use of the tool. Professional designers also use this bias. For instance, I might recognize that creating a custom font or illustration is not core to my solution, so I can employ an off the shelf font or illustration and focus, say, in the written content. Same principle. The problem is most people won’t even acknowledge or validate the essential aspects of the solution and just iterate mindlessly.

The issue is that UI design has different constraints compared to general graphic design, just like product design is not sculplture. Most UI designers only care about the visual aspects while neglecting the interactive aspect.

A whiteboard or a wireframing software would be better, because it lets you focus first on the interactive part. And once that’s solved, the visual part is easier.