Internet service providers’ DNS or third-party DNS providers often pose colossal privacy risks. They can use records of your DNS requests to track your activity and use them for marketing purposes (such as displaying personalized ads). A DNS can be a tool of censorship as well, with governments telling local DNS providers to block certain websites.
If your privacy is important to you - and it should be - private DNS becomes of paramount importance. And all Surfshark servers support private DNS.