Why do modern editions of As You Like It show "de Boys" instead of the correct "de Bois"?

Update: Apparently the latest Oxford Shakespeare agrees with me. I didn't realize this at the time of the post.

Summary: the surname "de Boys" in modern spelling editions of As You Like It is simply a mistake; "y" and "i" were interchangeable in the 16th century and the surname was always intended as "de Bois", the French word for forest. It is not an "Anglicization."

In his masterwork Shakespeare and Ecology, Randall Martin points out that the "de Boys" surname is a change from Shakespeare's source text. Thomas Lodge's 1590 Rosalynde, Euphues Golden Legacie  refers to the deceased father as "John of Bordeaux".

In As You Like It, the family name is spelled "de Boys". Here is the text from the First Folio, the only extant text of the play:

I am no villaine: I am the yongest sonne of Sir Rowland de Boys, he was my father, Orlando my Liege, the yongest sonne of Sir Roland de Boys.

Randall suggests that this is an Anglicization of the French word "bois" meaning forest. This appears to be the conventional wisdom, and most Shakespeare editors seem to agree, since they continue to use that spelling in 2018. However, this is simply a mistake.

As we saw in the case of Amyens/Amiens, "y" and "i" are used interchangeably in this play in the First Folio. "de Boys" is not an Anglicization, it is simply "de Bois" written with the y instead of an i, just like Amiens.

There are literally dozens of examples of this in EEBO. (I believe the same thing is true for French-language texts of the time).

Obviously, the surname "de Bois" (of the forest) relates to the plot of the play. It was completely intentional. By perpetuating "de Boys" until this day, they are lessening people's understanding of the play.

What motivates this kind of thing? Well there is some assumption that Shakespeare didn't speak, read, and write French. That probably motivates some of the thinking. Another is the dogma that the "Forest of Arden" in As You Like It relates to the Forest of Arden in Warwickshire since that is where William Shakespeare came from (and his wife's maiden name is "Arden" too!)

This belief is perpetuated even though the source text for the play is about the "Forest of Arden" and is clearly set in France, and Act 1 Scene 1 of As You Like It, Oliver describes his brother as "the stubbornest young fellow of France". People speak French in the play and there are many French names, including de Bois.

So, obviously, modern editions of the play with modern spelling should have "de Bois," since "de Boys" was simply a 16th century equivalent spelling of the same French word. QED.