I answered question 2, learn how to read before coming at me with that shit. Aleph One is the fan team.
Your orher two questions are that is Bungie and Sony. NOT Playstation, Sony. They are an independently operated part of Sony who's job is to make money for Sony by running their live service games anywhere possible, just as Lancresse, under Sony Music Group, also releases their stuff anywhere they can. As part of that they've openly let their fan community make a free Windows port of the original Marathon, which has been publicly worked on since before they were even acquired.
And since it is a free fan project with no dev involvement or support, its not going to go up on any pay to play console storefronts, as that would take development kits, which are not free.