We obviously know Chrome team is not doing things for security reasons, they are doing things for ad revenue reasons. But it's also true that blocking ads requires an insane amount of trust: The uBlock Origin author can choose to read your bank account numbers and passwords. (Although he is high profile enough this would be caught quite quickly.)

Arguably the problem is that Manifest V3 proposed removing an ad blocking capability without replacement, whereas I would argue just as popup blocking was a couple decades ago, it belongs as a first class browser feature, not outsourcing extremely sensitive capabilities to random outside parties. Browsers should not be operated by (or funded by.........) ad networks, and should built high quality, secure tools to filter unwanted content from their users.