What oversaturation? Apart from a handful of titles like Dusk and Ion Maiden, what FPS are deliberate throwbacks? This 'Prodeus' game certainly doesn't look like it's attempting to be that.
Compare that handful to other subgenres of retro indie games, like say 2d platformers/side-scrollers, which easily number in the thousands.
There's Overload, Amid Evil, Ion Maiden, Dusk, Project Warlock, Hellbound, Quarantined: Viscerafest, the Descent reboot (if being part of an actual old school FPS series counts), HellScreen, Apocryph, Intrude, this game...
That's counting games with actual hand-made levels, no procgen roguelite crap.
That may not seem like much, but then the total amount of indie singleplayer first-person shooters released per year isn't as large as the amount of side-scrollers released per year. So if you're into singleplayer first-person shooters which are actually about shooting, these are pretty much the only choices you have. The last indie shooters to really break the mold were Devil Daggers and DESYNC, the first one being a 10/10 arena survival shooter that realized the concept in a way no other survival mode shooter ever quite did, and the second one being an FPS with arena level design about killing things with style which was kind of rough around the edges, so I showed the developer my review of it and he told me on Discord that he was making a big redux patch for some time which might incorporate some of the things I said, so who knows how it's going to turn out in the future.
I don't believe that these throwback shooters are bad, or that being a throwback shooter makes them worse, god knows Overload is the best FPS released in the past decade or two, but I can already foresee how this trend is going to progress and how after a year or four we'll be completely sick of these kinds of games once the more soulless hacks start latching on. Even amongst these throwback shooters you will hardly find any examples which are innovative within the old-school style of FPS design. You can find more of that innovation in Doom WADs, I'd love to see a full game based on Demonsteele or Project MSX.
The last AAA shooter to break the mold would be nuDoom, but nobody even realized its potential. Up top everyone was too swept up with the hype of finally playing an FPS 'purely about action and no bullshit' (their words) while treating nuDoom as the herald of the return of the old-school, even though it played radically different from the old-school. Except nobody realized what. Almost nobody realized the potential of arena combat and the shift towards a more beat 'em up-esque approach to enemy combat and enemy design where you're locked in with highly mobile and reactive enemies. Almost nobody even acknowledged how nuDoom had the
least worst boss fights in any FPS.
Not even id software realized this.
Grognards shat on the game, unrightfully with the criticism that arena level design is inherently shit while subtly implying that Doom/Quake-style non-linear maze-like level design is The One And True Path For FPS Level Design, and rightfully because the actual implementation of arena level design and combat in nuDoom failed on many counts. I sincerely hope that id gets it properly right next time with Doom Eternal, though I doubt it well end up being a strong enough improvement over nuDoom for people to start noticing any excellence in design for game design youtube channel nerds to start making videos about it. Unless the Japanese step in to show their own approach to first-person shooters, or until maybe someone realizes how F.E.A.R. realized combat with hitscan enemies everywhere really well, then we're going to be stuck with developers whose only notion of what makes a good FPS is by copying Quake/Doom for quite some time.