Is there any reason this isn't on by default? I don't know exactly how it works, but to my understanding anti fingerprinting tech generally works better when everyone uses it (otherwise you stick out as the "anti fingerprinting" browser)
Every time you see a Captcha, you may have to do four or five to be considered "human" because the system struggles to determine who you are.
Is the tile fade-in also the system struggling to figure out who you are? No, it's vindictive. Punishment for not browsing the web the way google wants you to.
Here is a video of the fade-in in action: https://youtu.be/zGW7TRtcDeQ?t=89
(Note that you do not need to be on a shared IP to experience this. Merely using firefox with resist fingerprinting and a adblocker is enough to trigger this behavior on an IP google normally 'trusts' when using chrome.)
Okay, I agree that's punitive. I've never seen a fade that slow, so it must be at the lowest levels of trust.
I have a static IP address, and Google will happily give me a not-dick captcha if I use another browser without anti-tracking features enabled (even with a clean profile).