Computers are very vulnerable to so called "cold-boot attacks", which is where the attacker unplugs the RAM memory modules from the running computer and into their own device, that keeps the RAM memory modules powered, but reads out cached disk content and disk encryption keys loaded in the kernel. The problem here is that the RAM memory modules are easily removable, and won't lose their content for several seconds after losing power, thus can be moved that way, but also that they aren't encrypted in any sense.
My understanding is that on Pixel phones, the RAM memory modules are soldered on, and thus cannot be easily removed. But my understanding is also that they are still entirely unencrypted. What prevent well-invested attackers from opening up the running phone, adding some wires to "virtually" replug the RAM memory module from the phone to their own device, and then read out all cached file content and loaded disk encryption keys? Why do we not hear about attacks like this, but instead that they are exploiting vulnerabilities, which should supposedly be much harder to do?