I am very well aware of the CD-i games, though I never played Zelda’s Adventure (just the other two). I’m also aware of the PC remakes and the very well done Arzette.
While I don’t know all of what the dev (john-lay) put into this, I don’t think “port” is the right word here, unless he actually used the source code from the CD-i game (is this even available anywhere?). I’d say that remake/demake would be more applicable. But, that’s more of a semantics argument, I suppose.
Even if it’s an unpopular opinion, I still feel this would benefit from “feeling” more like a main Zelda game.