That combined with the increasing crackdown by the consumer on blocking data tracking raises serious questions on the long term viability of the business models of some big players in the industry.
For years myself and other engineers have been warning the product owners that third party user tracking's life span is very much finite - Firefox was going to block 3rd party cookies by default several years back, but walked it back because Google weren't ready for that and threatened to withdraw the money Mozilla makes from them, but it was the sign of the end times.
Now that Google can identify you with reasonable probability without using cookies, they won't hold Firefox back, they don't need to, and it suits them to roll out the third party blocking in Chromium, alongside browser cache partitioning to avoid the classic circumventions - ETags, steganographed PNGs etc. as first implemented by Safari. UA strings, often used in fingerprinting, are also not long for this world.
And of course, now that Google has a solution that doesn't require cookies or fingerprinting, Chrome is all about that privacy lol - the fact that it hurts Google's competitors is merely happy circumstance.
The amount of panic in adtech companies now is hilarious because they chose to mimic an ostrich until the browsers left them no choice - but they're still flailing around and demanding devs try to find alternatives to 3rd party cookies.
The cookie based user tracking paradigm is dead, but there's a shit ton of people, especially in DSPs and DMPs whose salary relies on them not believing that.
Luckily, the partitioning of browser caches on a per domain basis as pioneered by Safari has now made its way to Firefox (I think it's been released) and I presume will eventually be turned on by default in Chromium: https://www.chromestatus.com/feature/5730772021411840
> A clear funnel with established conversion rates, check
Is it checked? > 20% of people hitting our landing page block Segment which then blocks a portion of our analytics. It's pretty hard to get the full picture on your users, especially those coming from ads.