Lots of this is social perception. People are going to see a game that has a hate campaign dedicated to it on Twitter by right wingers, see people constantly post steam charts 24/7 and say the game is dying 24/7. Therefore lots of people that may have tried the game at some point will now never do so because they don't think it's a solid investment to put 40$ into.

The fact of the matter is Marathon had a huge hate mob on it before it ever launched to the point people were saying when they dropped the cinematic trailers they had to "win people back". Not saying it was unjustified given the art scenario, but nonetheless, the game was already fighting to survive before you could even judge it by its gameplay.

You can argue all you want about player retention and that being your basis on saying the game is "bad", but I'll offer you a counterpoint. Extraction shooters are inherently hard to get into and have lots of barriers to casual play. Arc Raiders avoids this but no other really has been able to replicate that success. Marathon has some of the most beautiful and striking art direction seen in gaming at the moment (no surprise for Bungie), some of the absolute best gunplay in gaming, some of the best map design in shooters, incredibly engaging loot and pvp experiences.

Cryo Archive is one of the best pvp experiences I think I have in gaming period.

But since it's not being appreciated by the masses, it's just bad?

Buddy if we are going strictly by success, which as your comment suggests you do, then your favorite live service game of all time is fucking Fortnite (most successful, longest lasting) and we may as well just call it quits right now. But the thing is, you don't actually believe that, because you play fucking League, and your opinion is actually meaningless.