Tax might have been a part, but very far from all of the difference. The dollar=euro was there decades before the introduction of the mandatory 2 year minimal guarantee.

Also if your product can't handle 3 years of use then maybe you shouldn't be selling it

The point is that is factored into the cost. Regardless of what you plan for, you need to offer a 3 year warranty. That has a non-zero cost, regardless of how reliable or awesome you make your product.