Genuinely asking, why is it considered bad? If it is done right, it will guide the customer better on whether they want something like it. We all see the photos/reviews on google maps before going inside a restaurant.
Pictures on a menu implies that the menu rarely changes - menu creation is expensive and slow - and has standard offerings. This then means that food is likely to be less fresh, less seasonal, and more likely to be precooked in large batches and frozen/reheated. In short, it is a red flag for systemic cooking rather than artisinal cooking.
You find that most higher-class restaurants have a one-page menu, with a soup of the day, 4-7 dishes, and maybe a dessert, with the menu being written once a day and clear about what you get.
You find that most higher-class restaurants have a one-page menu, with a soup of the day, 4-7 dishes, and maybe a dessert, with the menu being written once a day and clear about what you get.