How to get Firefox ad blocking performance from Safari?

Safari’s content blocking functionality provides an API for third-party apps to provide block lists. Safari provides various functionality for blocking cookies and preserving privacy, but does not perform ad blocking by itself.

Get an extension for Safari (such as from the App Store or elsewhere online) that provides a content blocking extension and configure the Safari extension to block ads.

Apps tell Safari in advance what kinds of content to block. Because Safari doesn't have to consult with the app during loading, and because Xcode compiles content blockers into bytecode, this model runs efficiently. Additionally, content blockers have no knowledge of users' history or the websites they visit.

An alternative to using Safari's content blocking, is to use AdGuard for Mac. This runs as a separate process and intercepts network traffic from any app (you specify which apps). I have mine configured to block ads (and trackers) in all browsers, News Explorer (my news reader) and DEVONthink.

By design the app is watching all browsing and all components in a web page. So you have to trust AdGuard to maintain your privacy, but there has been no suggestion of AdGuard breaching that trust. But you are already trusting Apple and Mozilla.

For me, the benefits of a system-wide ad and tracking blocker outweigh any risks around trust.

You can achieve this result using, for example, PiHole. You use it as DNS server for your home connection and all devices connecting to the internet via your home network will have ads removed. This is the result I get for the site you have shown:

This is not Mac or Safari specific, works with any computer and any browser. It also gives a nice dashboard to check which devices connect to your networks and how much dns requests were blocked as ads.