Small businesses have always needed images they could not obtain. Photography costs money, stock libraries look like stock libraries, and using a picture found through a search engine is a copyright problem waiting to be noticed. Being able to generate an illustration on demand removes a genuine constraint, and for backgrounds, diagrams, social posts and decorative material it is straightforwardly useful.
The care needed is about the difference between decoration and evidence. An abstract image at the top of an article claims nothing. A photograph of a finished kitchen on the page selling kitchen fitting claims that you fitted it. If that image was generated, the claim is false, and the fact that it was easy to make does not change what a customer reasonably understands it to mean. The rule that holds up is simple: anything presenting itself as your work, your premises, your team or your product should be a photograph of the real thing.
This extends further than most people first assume. Pictures of staff who do not exist, premises you do not have, or a product shown with details it does not possess are the same category of problem, and in several jurisdictions the last one is a consumer-protection matter rather than a question of taste. The risk is not usually a complaint about the image; it is a customer arriving expecting what they were shown.
There are practical wrinkles worth knowing. Generated images can reproduce recognisable logos, faces and trademarked designs from what the tool learned, and using such an image commercially is a problem regardless of how it was produced. Rights in the output vary by jurisdiction and by service, and some make it hard to claim exclusivity - which matters if the image becomes a logo or anything else you expect to own. Checking the terms of whichever tool you use is a five-minute job and is worth doing before the image goes on a sign.
Used inside those lines, the value is real and the guidance is short. Generate freely for anything illustrative, decorative or explanatory. Photograph anything factual. When a picture would be doing the job of proof, take the photograph, because that is the only version of it that is actually true - and it is the version a customer is entitled to assume they are looking at.