Yeah 25 years ago people said stuff like that about fingerprint scanners, and then they got hacked by literal gummy bears:

https://www.theregister.com/2002/05/16/gummi_bears_defeat_fi...

For 2020's-era palm scanners you don't have to replicate a 3D hand -- just like a video chat doesn't replicate my 3D face. You just have to emit photons (some of them infrared, yes) in the correct pattern. The hack won't look like a 3D-printed hand, it'll look like a display panel that works beyond visible wavelengths. It'll probably be some device developed for a totally unrelated market, and then one day "whoops, all those palm scanners are 0wn3d" (natürlich auf Deutsch) will be a talk title at CCC.

But all this is academic. The real problem with biometrics is that when your password is a body part, you can't change your password.