Based on the vidoes I've seen, Doom eternal strikes me as being....I dunno, I feel a bit mixed on this. One the one hand, Doom eternal itself is by all acounts mostly fine, and everything works as intended. But I'm not entirely sure the intended route is the best one.
For example, the new system where you can cripple monsters by targetting key weak points to disable their weapons. That's pretty cool. What's perhaps not so cool is it's not so much a "can" do as it is a "must", because if you don't shoot the tail off every arachnotron, the flamethrower off of every mancubus, etc, they'll wreck you in short order. It doesn't really feel like a clever tactical move on your part and starts feeling like a chore. It reminds me of how bulletstorm combat started to really turn into a grind whenever you had to constantly do special kills to get enough points to buy more ammo, instead of just being able to shoot people and move on, or to just play the game how you want to.
The same thing comes up with the ammo/armor/health system. Ammo particularly, because now that the chainsaw basically has infinite fuel, getting more ammo is just a chore now. You have effectively unlimited ammo, you just have to push a button every once in a while to maintain it. It starts feeling really, really regimented and managed, which is ironic for a game that's trying to get away from the modern shooter system of highly regulated, samey combat.
The gameplay also keeps escalating, and I'm not sure how long the franchise can maintain that. Doom Eternal's combat is even more frantic and fast paced than 2016 in general. It starts out more intense and peaks higher, and adds more and more stuff. In 2016, you had to manage just the combat, your weapons, your ammo, and maybe your grenades but people tend to not use those because you have that on your shotgun and it's way better. In Eternal, you have all that, plus more intense combat, plus having to do some precision shooting mid combat, plus your dash, plus your shoulder gun which is now key to the health/armor system, plus your blood punch. It's borderline too much, and I can't imagine they can go up from here because then it will be too much.
There's also the doom slayer as a character. Eternal really crystallized something that 2016 had started. In Doom 1 through 3, you were just a guy. Maybe a more stubborn, lucky, skilled, or iron willed guy than average, but still at core just a regular guy. Anyone could have been doomguy. The Doom Slayer is not just a guy. The Doom slayer doesn't save the world because he's just lucky, because he's more experienced, because he was the right man in the right place at the right time. The Slayer saves the world because he's just flat out better than anyone else, because he has super armor and super weapons and VEGA and a doom fortress and superpowers and access to all this stuff that no one else has. In 2016, you could go "eh, they had those elite guards, and they had all these weapons, and they just got sucker punched, if they'd had a bit more time to reorganize, maybe they could have won without you". In Doom Eternal, you are the only person that could possibly save the earth, the best that regular people can do is not die while you do all the work. And there's something....off about that narrative.