That greatly misrepresents what the article says; really Mozilla acquired a company with a mission to get user data out of the advertising industry, which happened to be founded by former Meta employees:
Two years after leaving Meta to launch their own privacy-focused ad measurement startup in 2022, Graham Mudd and Brad Smallwood have sold their company to Mozilla. ...
Mozilla had initially been talking to Anonym, which uses privacy-enhancing technologies to build measurement and targeting solutions, about a potential partnership.
“But that quickly turned into, ‘Wow, our missions are basically the same,’” Chambers said. “We realized that together we could move a lot faster.”
That shared mission is predicated on the notion that advertising and privacy are not – or at least don’t have to be – mutually exclusive.
“We both believe that privacy-preserving technologies are a critical part of the solution to the privacy problem in digital advertising,” Chambers said. ...
Anonym also has technology that allows ad platforms and advertisers to securely share encrypted impression and conversion data within a trusted execution environment for attribution, causal lift measurement and lookalike modeling. (A trusted execution environment is the secure area of a main processor where code can be run safely and in isolation.)
To be fair, the major ad platforms have long offered attribution and measurement solutions, Mudd said. “But they required the data to come into their system,” he added. “In this world, that doesn’t have to happen.”