Hi @beee
Yes, to be able to upload the images using wp uploader, the user role should have at least the upload_files capability. Sometimes, they also need to have the create_posts, delete_posts, and edit_posts capabilities.
If you don’t want to use the wp-uploader, you can always use the basic uploader like what you have done. But I’m afraid it won’t work for the gallery field.
As a workaround, you can try to use the repeater field instead. That way, you can create a repeater with an image field as the subfield and your visitor can upload the images one by one. If you want to, you can also convert the data from repeater field to gallery field by using acf/save_post action.
I hope this helps 🙂
