At first it sounds insane that Google would do such a thing since while ad blocking is growing, enabling the feature natively especially by default would incredibly increase the number of ads blocked. My guess is, that where other blockers by default can easily block all google ads, Chrome blocker would not block Google Ads because it would classify them as acceptable. And Google would then hope that people would use…
The new model for content blockers in Safari is faster and a lot more memory efficient because they're compiled into byte code. Content blockers are also more secure and better for privacy because they have no knowledge of the browsing that users are doing. The content-blocking rules are only provided by third parties.
Google is probably doing this because it makes their browser faster—not because of some wild conspiracy to show more advertisements.
[1]: https://developer.apple.com/library/content/documentation/Ge...