Referencing something called "adaptive touch," the code mentions that "Touch sensitivity will automatically adjust to your environment, activities, and screen protector."
At present, Pixel 8 series devices have a screen protector mode that ramps up the sensitivity if you have a screen protector installed (your phone will usually detect if you have a protector in place on its own, but you can access this by tapping on "Display" in the settings menu). But the new "adaptive touch" seems to include that mode and more, adapting to its conditions in other ways.
What kind of environments or activities the display would adapt to isn't clear, but considering what kind of activities usually interfere with touch screens, it's likely to include rain or wet fingers, gloves, and cold. Like the screen protector mode, this would likely function by monitoring the touch screen and adapting to any changes.
Google hasn't officially said anything about the new feature, so we don't know what devices are getting adaptive touch. But given that the Pixel 8 and Pixel 8 Pro have the screen protector mode, it's almost certain the feature would start there. A rollout date hasn't been announced either, but once things start popping up in Android beta code, it's usually not too long before they're released to the public.