The scanner on the s20 is still total garbage! I just switched from a s9 plus to a s20 plus and it's been a month and I regret it. I have to focus so much on the unlock process of this phone that it takes away the joy of using it because I have to go through multiple failed unlock attempts before I can get in the phone.
And yes I know all the tricks of adding fingers etc so let's not even go there.
Samsung should just push a software update that cuts the "security" by 50% and makes the scanner more forgiving or even more give the user the option of making it supper forgiving just so that the it never fails the unlock. It's unbelievable how your QA gave this a pass.