Luckily, one Pixel fan on Google+ discovered that if you disable both WiFi and LTE radios before putting your Pixel to sleep, battery drain seems to be drastically lower, or almost totally eliminated.
Granted, it’s probably easier just to completely shut down the Pixel before closing the lid, if you’re really worried about battery drain while sleeping. Since the Pixel only takes a few seconds to cold boot, you’d probably spend more time navigating through your settings menu to turn on WiFi and LTE.
But perhaps more importantly, this discovery means that the problem isn’t necessarily a hardware issue. Instead, it looks like this is something Google might be able to fix in a future software update to the Pixel – that makes me less worried, and more confident in Google’s promise that Chromebooks do in fact get better over time.
If battery drain while sleeping is an issue you experience on the Pixel yourself, be sure to report this problem to Google, using the Send Feedback option in the menu (or just press alt + shift + i).