Mostly out of curiosity, what version of King's Quest 1 is on Steam? It's impossible to tell from Steam's store page, and I refuse to go on Steam's discussion boards to ask there. (If you've spent time on one of those boards, you might understand why...)

Ok, so I went out and bought it on Steam (i.e. the KQ Collection) and can now answer my own question. Just like with Steam's Space Quest Collection, that download on Steam actually gives you access to two collections: the King Quest Collection and the King's Quest Legacy Collection. In the two collections, KQ2 through 7 are identical but KQ1 is different: the AGI original in the King's Quest Collection (not Legacy), and the SCI remake in the King's Quest Legacy Collection.

(And, no, I am not urging people to choose Steam over GOG. I am just here to note where the SCI remake can be legally acquired.)