My iPhone 15 Pro Max had the same (Black screen) issue after charging overnight. This was the first time I left the phone charging on my office charger all night. Usually, it is charged by my bed. This was super annoying as I got up early to get some work done and found the solution 30 minutes later. If you tap the VOLUME UP key and then tap the VOLUME down key, next hold the button on the right side for 10 seconds or until the Apple logo appears it will fix the problem. BTW, when I was trying to get to forums to find the problem, I was asked for a verification code, luckily I plugged in a new iPad yesterday so it came up there. What if I didn't have another Apple device and could not get the verification code as my phone had this black screen?
Apple, I have been a fan since the Macs with green screens first came out. Fix this problem. You are better than this. You make my life easier, not harder.