The new Iphone 8 still has the fingerprint button. It is just the X that has face ID option. BTW, fingerprint sensors may not work on senior citizens. My Dad has that problem...
The Apple "fingerprint" reader actually doesn't read fingerprints, it reads the subcutaneous fat valleys and ridges underneath the skin of the fingers. Older people start to lose those fat ridges which what supports the skin. The pattern slightly changes as the body reclaims the fat exaggerating the valleys. Extreme dieters can have this issue as well. Try re-doing the initial imprinting of his fingers. That could solve your dad's problem with the TouchID unlocking his iPhone.
The Apple "fingerprint" reader actually doesn't read fingerprints, it reads the subcutaneous fat valleys and ridges underneath the skin of the fingers. Older people start to lose those fat ridges which what supports the skin. The pattern slightly changes as the body reclaims the fat exaggerating the valleys. Extreme dieters can have this issue as well. Try re-doing the initial imprinting of his fingers. That could solve your dad's problem with the TouchID unlocking his iPhone.
I’ve had OLED and AMOLED screens for years...I can’t go LCD. Does the iPhone 8 have OLED?