On the left, a very worn blade from a roughly decade-old Fiskars paper trimmer. On the right, one of the replacement blades you can get at Staples. Note the extra lugs stopping the new-style blades working with the old-style cutters? Bet they think they’re really clever little Fiskars for coming up with that planned obsolescence move.
It’s nothing that a steady hand and a rotary tool can’t fix, though …