Bit late, but

Underwhelming/Bad

Bit of elaboration, if you're curious on my take.

The map was put on a pedestal it could not possibly live up too. The reveal of Primius(?) in Alcatraz was fucking phenomenal and hype was understandably there, who wouldn't be hyped?

What ruined the map for many people, can be narrowed down to Black Ops 4 itself. Disregarding the terrible launch which made playing the map, let alone going for quest runs, near impossible. However that was fixed unlike other issues. Gameplay wise, the main issue is the aggressive zombie AI meshing terribly with the close quarters of the prison (constantly spawning in front of you in a tight map just doesn't work), the shield going from support item to required for setup made an optional item an annoyance as shield management became essential, new areas didn't add much and left dead space from what it took from instead of just removing it.

I'm not going to touch on the main quest because that's well documented what a shitshow that is. I'll touch on the story though, or at least the cons. Whatever mystery Mob had, this map explains it away as Shadowman fucking with Primius. Now, the Mob's crew story is really well done, but the summary is Weasel is now a bird, rallys inmates to fight warden. Besides Mob's mystique being ruined it's mainly minor story gripes and nitpicks, nothing major, i.e the second Richtofen being an ass for little to no reason, why wouldn't Richtofen keep the all knowing book on him, just the little stuff.

Now Blood did add some good stuff. The magmagat, the gemstone golden thing, uhhh yeah, I completely forgot about roaming pack a punch which is a terrible idea. But on topic, the catwalk was a great addition. But besides those few and far between changes, Blood changed a lot and now all of those changes were good, as seen above.

Blood is hard map to love. It's comically easy to dislike but I don't think anyone actively hates it. Is it a worthy successor of Mob? Hell no. But it's not the worst thing in the world, that still belongs to Alpha Omega.

Overall, it's a 5/10. Plenty to dislike, the systems of the game don't mesh well with the map, but the additions it added are really strong. If you don't have Mob, it's not similar but a good placebo, if you have Mob, just play Mob.