No all copies are BERENSTAIN Bears not Barenstein, and that's what it always was. I think people just pronounced it Berenstein - and you can't remember that it was always actually Berenstain NOT BERNSTEIN. If you looke up vintage copies you can't find one that is spelled Bernstein...because it never was...I think this guy is just putting out a false conspiracy theory.
Here's some real conspiracy...common nursery rhymes with racist origins that have been whitewashed through the years....