The changes are to limit the tries to unlock to 5 to reduce the possibility of getting forced to press your finger on the sensor by other people.
Here in the Reddit you can read that this is a security feature and you simple have to quickly press a wrong finger 5 times to enter lockdown mode.
In reality that is not possible. After 3 false attempts the lock screen resets and you have to swipe up again, making it impossible to quickly do the false attempts. That takes a few seconds and you have to look at the screen and after that you still have 2 tries.
Possible solutions I have thought about:
Limit the count to 1-2 without the gesture in-between: the sensor on my phone is very good anyway and if my finger doesn't get recognize because of dust, water, ... It won't be on the 4 time either.
Add options to quickly enter lockdown: for example a new button next to the fingerprint field, that you can quickly press in such a situation or a sshortcut like press at the field and then swipe down while holding, or press the power button 3 times on lock screen.
Add duress finger prints that reset or just reboot the device, for example you put your right thumb there as it is the finger most likely to be tried out first.
Disclaimer: I am not dependent on grapheneos being fully safe, as I just use it to break internet access by apps and sideloading, but that is an issue I have read on so many articles and videos that I have to display my opinion on it.