Marathon makes a great first impression but, very quickly, what's not there becomes as impactful as what is. Having praised the gameplay extensively, I have to pivot and also point out that everything it is doing is very ordinary, but executed well.
Although I enjoyed playing the game, it was very evident that it didn't have a hook; a special something that will help it stand out from the crowd; an X-factor that gives it a fighting chance in a crowded world of multiplayer games that demand all of your time and attention. I wouldn't go so far as to say it felt soulless, but it definitely felt like something was missing, that one more ingredient to bring it all together. Without that, numerous other games popped into my head as more exciting prospects.
Admittedly, most of those games aren't extraction shooters, but when it comes to making commitments, I have to assume a large portion of the intended audience isn't going to make that distinction, so why should I? Ultimately, regardless of genre, Marathon will be competing for the same time and attention that people have given, and are still giving, to Overwatch, Apex Legends, Warframe, Escape from Tarkov, Hunt: Showdown, The Division 2, Valorant, Destiny, Marvel Rivals, Fortnite, Call Of Duty, Counter-Strike, and many others.
Those are games that people have hours, days, months, and years of investment in, so it's going to take something special to make them even consider switching or splitting attention, let alone pull them away. As it stands, I don't think Marathon currently has that.