If Face ID was set up, it will always use that first. Only if the face is not recognized or you force that passcode option swiping up before it's done scanning, will it offer the Passcode entry screen.
Again, you can check in Settings ➜ Face ID & Passcode for what is set up.
If you ever set up Face ID, then it's always active. The only indication Face ID is being used is a small green icon at the top of the screen.
If you have an older iPad Pro, it. may be using Touch ID, but the general function is the same. When turning on the iPad using the sleep button / Touch ID sensor it will automatically scan the finger and if recognized unlock the device automatically. Again, you can force the passcode if you swipe up faster or are not pressing the power button to turn it on or are using a different finger than the one that was set up.
This has not changed in many years. What probably happened is you forgot you actually did set up Face ID or Touch ID and the system is now scanning your face or finger faster than before so there is no time to get the Passcode option, or it simply recognizes you better than the previous iPadOS version.