In your original comment, you’d said “toxic”. toomuchtodo was right to note exactly what your source explains: they’re mostly recyclable (though many places aren’t ready for the blades because they’re so big!) and if not they can be scrapped and left in a landfill. Toxic means something specific, and isn’t just “can’t be recycled”.

Apparently it's just extra fast replacement cycles due to the fact that the original designs weren't thought of this way.