There is no chance whatsoever of box set being replaced by the more correct form boxed set. So stop seething about it and causing yourself distress.
The form, boxed set has been in use for 125 years or so, but the Oxford English Dictionary has dug up a reference from Wisconsin in 1969 to a ‘box set of tumblers’. Admittedly, binge-watching a set of tumblers for hours on end would be a minority interest.
The triumph of box set is partly a matter of phonetics. In ordinary speech the d after the s sound in boxed set is hardly out before the poor old tongue gets round to hissing the initial letter of set.
There is an analogy here with sixth. I have heard people complain of news-readers or actors on television mispronouncing sixth. The tendency is to say sicth. We may all swear that we say sixth, but recordings suggest otherwise. It has never been a word to be pronounced phonetically. The Elizabethans were not too hot on the th sound. In the First Folio of Shakespeare, for example, the names of three history plays are spelt Henry the Sixt. So it seems to be a choice between the x and the th. You can’t have both.
The opposite tendency is to be seen in terraced houses. That seems to me the prevalent form. Keen pedants insist that it implies they are terraced like the Hanging Gardens of Babylon. To be sure, Jane Austen wrote of a ‘Terrace House’ and James Joyce wrote it as one word. An interesting anomaly, which the OED caught up with in 2007, has been to use terrace to mean just one house in the terrace.