Shortcodes themselves do not directly affect SEO, but how they are used and the content that they generate can potentially impact SEO. If the shortcodes generate high-quality, relevant content, then it can positively impact SEO. However, if the shortcodes generate low-quality or irrelevant content, it can negatively impact SEO. Additionally, the use of excessive shortcodes or the use of shortcodes to hide or obscure content can also have a negative impact on SEO. It's important to keep in mind that search engines like Google prioritise high-quality, relevant, and user-friendly content, so it's best to use shortcodes in a way that supports these goals.