The same is happening to me. My iphone 16 pro battery drains within no time. Charging it to 100% but It doesn’t even lasts for around 17-18 hours. I’m using it normally no gaming, less video streaming etc. yesterday charged my phone to 100%. One FaceTime call for around 1 hour and battery percentage gone below 75%. My iPhone 14 Pro battery health was around 87%, 100% charge lasts more than 24 hours with video streaming, browsing social media, listening music etc. But iPhone 16 pro being very new phone it is not the case. Battery drains so fast.
The performance, battery life and overall stability is far worse than my iPhone 14 Pro.
Apple must look into this.