The one place you need to look is the apps you have installed draining the battery. This is done by going to Setting s > Battery, then scroll down to view Battery Usage by Apps usage over the last 24 hours. Feel free to provide a screenshot if you wish. I can almost guarantee you have Meta apps there showing the battery usage due to Background Activity.
This will persist even if you are not using the apps. Meta is well aware of the problem and have state that they have updated their apps that provided an improvement, but it clearly has not been resolved. Snapchat has been seen as a battery abuser as well, but not nearly as bad as the Meta apps.
It is not your iPhone 16 that is the problem, and happens on other devices as well including Android phones as seen in their support forums.