Quick tip to disable dynamic sitelink in Google Ads: If you want to turn off any automated extension, you should open the Automated Extension list page in Google Ads, and then Click More > Advanced Settings to open an interface to turn on/off any automated extension as per your requirement.
There can be many reasons to disable an automatic extension. For example, sometimes the client’s website may not have been updated with new information and you may not want to show pages other than the landing page, so you might not have created any sitelink extension. In such a scenario it would be best if you would also disable the dynamic sitelink feature, to make sure that Google ads does not show any sitelinks on it’s own.