Well, these are separate concerns. If you have a document, with no interactivity, using just standard elements, but lots of different themes, then separating into content and style makes perfect sense.
And I’d prefer if we could go back to that as much as possible.
Yes, a general template defined in an external style sheet or whatever format makes sense. However, revealing a message when there is an error, for example, is business logic and should be defined in code - be it styled components or something else.
And I’d prefer if we could go back to that as much as possible.