See: http://paleojudaica.blogspot.com/ for serious questions about the authenticity of these lead tablets.
I have read some of the arguments.
They seem to hinge on similarities of depictions on coins of the era among other things.
The maker of these plates might have used the coins as a reference or they might have been actually used a part of the mold in the original.
I am not really interested in whether they are fake or not. That will be proven one way or another scientifically, not by ‘consensus’ opinion.
If they are real, it won’t change much of today’s world.
If they are fake, it won’t change any of today’s world...............